Remove WebKit::Platform dependencies from cc

cc/scoped_thread_proxy.cc

Index: cc/scoped_thread_proxy.cc
diff --git a/cc/scoped_thread_proxy.cc b/cc/scoped_thread_proxy.cc
index a181270384c4b7555c90e95d74625383bace6eb2..9391e3bb8f009e9a0d25a5a5dcfe22a91737f0b4 100644
--- a/cc/scoped_thread_proxy.cc
+++ b/cc/scoped_thread_proxy.cc
@@ -6,9 +6,11 @@
 
 #include "cc/scoped_thread_proxy.h"
 
+#include "base/bind.h"
+
 namespace cc {
 
-ScopedThreadProxy::ScopedThreadProxy(Thread* targetThread)
+ScopedThreadProxy::ScopedThreadProxy(cc::Thread* targetThread)
     : m_targetThread(targetThread)
     , m_shutdown(false)
 {
@@ -18,4 +20,27 @@ ScopedThreadProxy::~ScopedThreadProxy()
 {
 }
 
+void ScopedThreadProxy::postTask(const tracked_objects::Location& location, base::Closure cb)
+{
+    m_targetThread->postTask(base::Bind(&ScopedThreadProxy::runTaskIfNotShutdown, this, cb));
+}
+
+void ScopedThreadProxy::shutdown()
+{
+    DCHECK(m_targetThread->belongsToCurrentThread());
+    DCHECK(!m_shutdown);
+    m_shutdown = true;
+}
+
+void ScopedThreadProxy::runTaskIfNotShutdown(base::Closure cb)
+{
+    // If our shutdown flag is set, it's possible that m_targetThread has already been destroyed so don't
+    // touch it.
+    if (m_shutdown) {
+        return;
+    }
+    DCHECK(m_targetThread->belongsToCurrentThread());
+    cb.Run();
+}
+
 }