cppgc: Force inline Member

With pointer compression enabled the compiler may not inline some Member
functions on some platforms, because Member stores and loads become
slightly more expensive. Inlining is however important with pointer
compression - it allows to further optimize the code by eliminating
the global load.

Bug: chromium:1325007
Change-Id: Ia37d223e78853a8218e0b2732a3f08aa58929000
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3756141Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81648}

include/cppgc/internal/pointer-policies.h

@@ -27,11 +27,11 @@ class WeakMemberTag;
 class UntracedMemberTag;
 
 struct DijkstraWriteBarrierPolicy {
-  static void InitializingBarrier(const void*, const void*) {
+  V8_INLINE static void InitializingBarrier(const void*, const void*) {
     // Since in initializing writes the source object is always white, having no
     // barrier doesn't break the tri-color invariant.
   }
-  static void AssigningBarrier(const void* slot, const void* value) {
+  V8_INLINE static void AssigningBarrier(const void* slot, const void* value) {
     WriteBarrier::Params params;
     switch (WriteBarrier::GetWriteBarrierType(slot, value, params)) {
       case WriteBarrier::Type::kGenerational:
@@ -48,8 +48,8 @@ struct DijkstraWriteBarrierPolicy {
 };
 
 struct NoWriteBarrierPolicy {
-  static void InitializingBarrier(const void*, const void*) {}
-  static void AssigningBarrier(const void*, const void*) {}
+  V8_INLINE static void InitializingBarrier(const void*, const void*) {}
+  V8_INLINE static void AssigningBarrier(const void*, const void*) {}
 };
 
 class V8_EXPORT SameThreadEnabledCheckingPolicyBase {
@@ -90,7 +90,7 @@ class V8_EXPORT SameThreadEnabledCheckingPolicy
 
 class DisabledCheckingPolicy {
  protected:
-  void CheckPointer(const void*) {}
+  V8_INLINE void CheckPointer(const void*) {}
 };
 
 #ifdef DEBUG