ifdef out unused functions from base/threading to prevent dependencies.

diff --git a/base/threading/platform_thread.cc b/base/threading/platform_thread.cc
--- a/base/threading/platform_thread.cc
+++ b/base/threading/platform_thread.cc
@@ -4,7 +4,9 @@
 
 #include "base/threading/platform_thread.h"
 
+#if !defined(MOZ_SANDBOX)
 #include "base/task/current_thread.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "base/threading/thread_id_name_manager.h"
 #include "base/trace_event/trace_event.h"
 
@@ -14,6 +16,7 @@
 
 namespace base {
 
+#if !defined(MOZ_SANDBOX)
 namespace {
 
 constinit thread_local ThreadType current_thread_type = ThreadType::kDefault;
@@ -55,12 +58,14 @@ std::optional<TimeDelta> PlatformThreadBase::GetThreadLeewayOverride() {
 #endif
   return std::nullopt;
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 // static
 void PlatformThreadBase::SetNameCommon(const std::string& name) {
   ThreadIdNameManager::GetInstance()->SetName(name);
 }
 
+#if !defined(MOZ_SANDBOX)
 namespace internal {
 
 void RemoveThreadTypeOverride(
@@ -69,4 +74,5 @@ void RemoveThreadTypeOverride(
 }
 
 }  // namespace internal
+#endif  // !defined(MOZ_SANDBOX)
 }  // namespace base
diff --git a/base/threading/platform_thread.h b/base/threading/platform_thread.h
--- a/base/threading/platform_thread.h
+++ b/base/threading/platform_thread.h
@@ -17,7 +17,9 @@
 #include <type_traits>
 
 #include "base/base_export.h"
+#if !defined(MOZ_SANDBOX)
 #include "base/message_loop/message_pump_type.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "base/process/process_handle.h"
 #include "base/threading/platform_thread_ref.h"
 #include "base/trace_event/base_tracing_forward.h"
@@ -248,6 +250,7 @@ class BASE_EXPORT PlatformThreadBase {
   // Gets the thread name, if previously set by SetName.
   static const char* GetName();
 
+#if !defined(MOZ_SANDBOX)
   // Creates a new thread.  The `stack_size` parameter can be 0 to indicate
   // that the default stack size should be used.  Upon success,
   // `*thread_handle` will be assigned a handle to the newly created thread,
@@ -289,6 +292,7 @@ class BASE_EXPORT PlatformThreadBase {
       Delegate* delegate,
       ThreadType thread_type,
       MessagePumpType pump_type_hint = MessagePumpType::DEFAULT);
+#endif  // !defined(MOZ_SANDBOX)
 
   // Joins with a thread created via the Create function.  This function blocks
   // the caller until the designated thread exits.  This will invalidate
@@ -303,10 +307,12 @@ class BASE_EXPORT PlatformThreadBase {
   // of a thread in current process from `from` to `to`.
   static bool CanChangeThreadType(ThreadType from, ThreadType to);
 
+#if !defined(MOZ_SANDBOX)
   // Declares the type of work running on the current thread. This will affect
   // things like thread priority and thread QoS (Quality of Service) to the best
   // of the current platform's abilities.
   static void SetCurrentThreadType(ThreadType thread_type);
+#endif  // !defined(MOZ_SANDBOX)
 
   // Get the last `thread_type` set by SetCurrentThreadType, no matter if the
   // underlying priority successfully changed or not.
@@ -464,8 +470,10 @@ void RemoveThreadTypeOverrideImpl(
     const PlatformPriorityOverride& priority_override_handle,
     ThreadType thread_type);
 
+#if !defined(MOZ_SANDBOX)
 void SetCurrentThreadTypeImpl(ThreadType thread_type,
                               MessagePumpType pump_type_hint);
+#endif  // !defined(MOZ_SANDBOX)
 
 }  // namespace internal
 
diff --git a/base/threading/platform_thread_posix.cc b/base/threading/platform_thread_posix.cc
--- a/base/threading/platform_thread_posix.cc
+++ b/base/threading/platform_thread_posix.cc
@@ -20,9 +20,13 @@
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/raw_ptr.h"
+#if !defined(MOZ_SANDBOX)
 #include "base/notimplemented.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "base/threading/platform_thread_internal_posix.h"
+#if !defined(MOZ_SANDBOX)
 #include "base/threading/platform_thread_metrics.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "base/threading/scoped_blocking_call.h"
 #include "base/threading/thread_id_name_manager.h"
 #include "base/threading/thread_restrictions.h"
@@ -30,7 +34,9 @@
 #include "partition_alloc/buildflags.h"
 
 #if !BUILDFLAG(IS_APPLE) && !BUILDFLAG(IS_FUCHSIA)
+#if !defined(MOZ_SANDBOX)
 #include "base/posix/can_lower_nice_to.h"
+#endif  // !defined(MOZ_SANDBOX)
 #endif
 
 #if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
@@ -59,6 +65,7 @@ size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes);
 
 namespace {
 
+#if !defined(MOZ_SANDBOX)
 struct ThreadParams {
   ThreadParams() = default;
 
@@ -167,6 +174,7 @@ bool CreateThread(size_t stack_size,
 
   return success;
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 #if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS)
 
@@ -313,6 +321,7 @@ const char* PlatformThreadBase::GetName() {
   return ThreadIdNameManager::GetInstance()->GetName(CurrentId());
 }
 
+#if !defined(MOZ_SANDBOX)
 // static
 bool PlatformThreadBase::CreateWithType(size_t stack_size,
                                         Delegate* delegate,
@@ -341,6 +350,7 @@ bool PlatformThreadBase::CreateNonJoinableWithType(
                              delegate, &unused, thread_type, pump_type_hint);
   return result;
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 // static
 void PlatformThreadBase::Join(PlatformThreadHandle thread_handle) {
@@ -361,6 +371,7 @@ void PlatformThreadBase::Detach(PlatformThreadHandle thread_handle) {
 // GetCurrentThreadPriorityForTest() implementations.
 #if !BUILDFLAG(IS_APPLE) && !BUILDFLAG(IS_FUCHSIA)
 
+#if !defined(MOZ_SANDBOX)
 // static
 bool PlatformThreadBase::CanChangeThreadType(ThreadType from, ThreadType to) {
   if (from >= to) {
@@ -387,6 +398,7 @@ ThreadType PlatformThreadBase::GetCurrentEffectiveThreadTypeForTest() {
 
   return internal::NiceValueToThreadTypeForTest(nice_value);  // IN-TEST
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 #endif  // !BUILDFLAG(IS_APPLE) && !BUILDFLAG(IS_FUCHSIA)
 
diff --git a/base/threading/platform_thread_win.cc b/base/threading/platform_thread_win.cc
--- a/base/threading/platform_thread_win.cc
+++ b/base/threading/platform_thread_win.cc
@@ -12,7 +12,9 @@
 
 #include "base/debug/alias.h"
 #include "base/debug/crash_logging.h"
+#if !defined(MOZ_SANDBOX)
 #include "base/debug/profiler.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "base/feature_list.h"
 #include "base/logging.h"
 #include "base/memory/raw_ptr.h"
@@ -75,6 +77,7 @@ void SetNameInternal(PlatformThreadId thread_id, const char* name) {
 #endif
 }
 
+#if !defined(MOZ_SANDBOX)
 struct ThreadParams {
   raw_ptr<PlatformThread::Delegate> delegate;
   bool joinable;
@@ -209,6 +212,7 @@ bool CreateThreadInternal(size_t stack_size,
   }
   return true;
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 }  // namespace
 
@@ -294,6 +298,7 @@ const char* PlatformThread::GetName() {
   return ThreadIdNameManager::GetInstance()->GetName(CurrentId());
 }
 
+#if !defined(MOZ_SANDBOX)
 // static
 bool PlatformThread::CreateWithType(size_t stack_size,
                                     Delegate* delegate,
@@ -317,6 +322,7 @@ bool PlatformThread::CreateNonJoinableWithType(size_t stack_size,
   return CreateThreadInternal(stack_size, delegate, nullptr /* non-joinable */,
                               thread_type);
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 // static
 void PlatformThread::Join(PlatformThreadHandle thread_handle) {
@@ -353,6 +359,7 @@ bool PlatformThread::CanChangeThreadType(ThreadType from, ThreadType to) {
   return true;
 }
 
+#if !defined(MOZ_SANDBOX)
 namespace {
 
 void SetThreadPriority(PlatformThreadHandle thread_handle,
@@ -486,6 +493,7 @@ void RemoveThreadTypeOverrideImpl(
 }
 
 }  // namespace internal
+#endif  // !defined(MOZ_SANDBOX)
 
 // static
 ThreadType PlatformThread::GetCurrentEffectiveThreadTypeForTest() {
diff --git a/base/threading/scoped_thread_priority.h b/base/threading/scoped_thread_priority.h
--- a/base/threading/scoped_thread_priority.h
+++ b/base/threading/scoped_thread_priority.h
@@ -13,7 +13,9 @@
 #include "base/location.h"
 #include "base/macros/uniquify.h"
 #include "base/memory/raw_ptr.h"
+#if !defined(MOZ_SANDBOX)
 #include "base/task/task_observer.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "base/threading/thread_checker.h"
 #include "build/build_config.h"
 
@@ -103,6 +105,7 @@ class BASE_EXPORT ScopedBoostablePriority {
   THREAD_CHECKER(thread_checker_);
 };
 
+#if !defined(MOZ_SANDBOX)
 // This wraps ScopedBoostPriority with a callback to determine whether
 // the priority should be boosted or not before every task execution.
 class BASE_EXPORT TaskMonitoringScopedBoostPriority : public TaskObserver {
@@ -127,6 +130,7 @@ class BASE_EXPORT TaskMonitoringScopedBoostPriority : public TaskObserver {
   ThreadType target_thread_type_;
   RepeatingCallback<bool()> should_boost_callback_;
 };
+#endif  // !defined(MOZ_SANDBOX)
 
 namespace internal {
 
diff --git a/base/threading/thread_restrictions.cc b/base/threading/thread_restrictions.cc
--- a/base/threading/thread_restrictions.cc
+++ b/base/threading/thread_restrictions.cc
@@ -5,9 +5,13 @@
 #include "base/threading/thread_restrictions.h"
 
 #include "base/check.h"
+#if !defined(MOZ_SANDBOX)
 #include "base/threading/hang_watcher.h"
 #include "base/trace_event/interned_args_helper.h"
 #include "base/trace_event/typed_macros.h"
+#else
+#include "base/trace_event/trace_event.h"
+#endif  // !defined(MOZ_SANDBOX)
 #include "build/build_config.h"
 
 namespace base {
@@ -253,6 +259,7 @@ ScopedAllowBlocking::~ScopedAllowBlocking() {
       << "tls_blocking_disallowed " << tls_blocking_disallowed;
 }
 
+#if !defined(MOZ_SANDBOX)
 ScopedAllowBaseSyncPrimitivesOutsideBlockingScope::
     ScopedAllowBaseSyncPrimitivesOutsideBlockingScope(const Location& from_here)
     : resetter_(&tls_base_sync_primitives_disallowed,
@@ -280,5 +287,6 @@ ScopedAllowBaseSyncPrimitivesOutsideBlockingScope::
       << "tls_base_sync_primitives_disallowed "
       << tls_base_sync_primitives_disallowed;
 }
+#endif  // !defined(MOZ_SANDBOX)
 
 }  // namespace base