Remove static thread pointers from CC

cc/prioritized_texture.cc

Index: cc/prioritized_texture.cc
diff --git a/cc/prioritized_texture.cc b/cc/prioritized_texture.cc
index 56d50f2b9701ca1e9b706b30404aa69989ca54f3..b76e736ac5338f26ceeed355ec5665ed9a32685c 100644
--- a/cc/prioritized_texture.cc
+++ b/cc/prioritized_texture.cc
@@ -153,7 +153,7 @@ PrioritizedTexture::Backing::~Backing()
 
 void PrioritizedTexture::Backing::deleteResource(ResourceProvider* resourceProvider)
 {
-    DCHECK(Proxy::isImplThread());
+    DCHECK(!proxy() || proxy()->isImplThread());
     DCHECK(!m_resourceHasBeenDeleted);
 #ifndef NDEBUG
     DCHECK(resourceProvider == m_resourceProvider);
@@ -166,19 +166,19 @@ void PrioritizedTexture::Backing::deleteResource(ResourceProvider* resourceProvi
 
 bool PrioritizedTexture::Backing::resourceHasBeenDeleted() const
 {
-    DCHECK(Proxy::isImplThread());
+    DCHECK(!proxy() || proxy()->isImplThread());
     return m_resourceHasBeenDeleted;
 }
 
 bool PrioritizedTexture::Backing::canBeRecycled() const
 {
-    DCHECK(Proxy::isImplThread());
+    DCHECK(!proxy() || proxy()->isImplThread());
     return !m_wasAbovePriorityCutoffAtLastPriorityUpdate && !m_inDrawingImplTree;
 }
 
 void PrioritizedTexture::Backing::updatePriority()
 {
-    DCHECK(Proxy::isImplThread() && Proxy::isMainThreadBlocked());
+    DCHECK(!proxy() || proxy()->isImplThread() && proxy()->isMainThreadBlocked());
     if (m_owner) {
         m_priorityAtLastPriorityUpdate = m_owner->requestPriority();
         m_wasAbovePriorityCutoffAtLastPriorityUpdate = m_owner->isAbovePriorityCutoff();
@@ -190,7 +190,7 @@ void PrioritizedTexture::Backing::updatePriority()
 
 void PrioritizedTexture::Backing::updateInDrawingImplTree()
 {
-    DCHECK(Proxy::isImplThread() && Proxy::isMainThreadBlocked());
+    DCHECK(!proxy() || proxy()->isImplThread() && proxy()->isMainThreadBlocked());
     m_inDrawingImplTree = !!owner();
     if (!m_inDrawingImplTree)
         DCHECK(m_priorityAtLastPriorityUpdate == PriorityCalculator::lowestPriority());
@@ -203,4 +203,11 @@ void PrioritizedTexture::returnBackingTexture()
         m_manager->returnBackingTexture(this);
 }
 
+const Proxy* PrioritizedTexture::Backing::proxy() const
+{
+    if (!m_owner || !m_owner->textureManager())
+        return 0;
+    return m_owner->textureManager()->proxyForDebug();
+}
+
 } // namespace cc