Remove WebKit::Platform dependencies from cc

cc/proxy.cc

Index: cc/proxy.cc
diff --git a/cc/proxy.cc b/cc/proxy.cc
index 317499c3721c2785caa6febe3ca1a45f4d4b3624..7b738aa5a5bd891ccfb5826cf51c579fb6d323e0 100644
--- a/cc/proxy.cc
+++ b/cc/proxy.cc
@@ -6,7 +6,7 @@
 
 #include "cc/proxy.h"
 
-#include "cc/thread_task.h"
+#include "cc/thread.h"
 
 namespace cc {
 
@@ -14,7 +14,6 @@ namespace {
 #ifndef NDEBUG
 bool implThreadIsOverridden = false;
 bool s_isMainThreadBlocked = false;
-base::PlatformThreadId threadIDOverridenToBeImplThread;
 #endif
 Thread* s_mainThread = 0;
 Thread* s_implThread = 0;
@@ -47,10 +46,9 @@ Thread* Proxy::implThread()
 
 Thread* Proxy::currentThread()
 {
-    base::PlatformThreadId currentThreadIdentifier = base::PlatformThread::CurrentId();
-    if (s_mainThread && s_mainThread->threadID() == currentThreadIdentifier)
+    if (s_mainThread && s_mainThread->belongsToCurrentThread())
         return s_mainThread;
-    if (s_implThread && s_implThread->threadID() == currentThreadIdentifier)
+    if (s_implThread && s_implThread->belongsToCurrentThread())
         return s_implThread;
     return 0;
 }
@@ -59,9 +57,9 @@ bool Proxy::isMainThread()
 {
 #ifndef NDEBUG
     DCHECK(s_mainThread);
-    if (implThreadIsOverridden && base::PlatformThread::CurrentId() == threadIDOverridenToBeImplThread)
+    if (implThreadIsOverridden)
         return false;
-    return base::PlatformThread::CurrentId() == s_mainThread->threadID();
+    return s_mainThread->belongsToCurrentThread();
 #else
     return true;
 #endif
@@ -70,10 +68,9 @@ bool Proxy::isMainThread()
 bool Proxy::isImplThread()
 {
 #ifndef NDEBUG
-    base::PlatformThreadId implThreadID = s_implThread ? s_implThread->threadID() : 0;
-    if (implThreadIsOverridden && base::PlatformThread::CurrentId() == threadIDOverridenToBeImplThread)
+    if (implThreadIsOverridden)
         return true;
-    return base::PlatformThread::CurrentId() == implThreadID;
+    return s_implThread && s_implThread->belongsToCurrentThread();
 #else
     return true;
 #endif
@@ -83,8 +80,6 @@ bool Proxy::isImplThread()
 void Proxy::setCurrentThreadIsImplThread(bool isImplThread)
 {
     implThreadIsOverridden = isImplThread;
-    if (isImplThread)
-        threadIDOverridenToBeImplThread = base::PlatformThread::CurrentId();
 }
 #endif