Enable removing uploads to evicted textures from texture upload queues.

cc/CCLayerTreeHost.cpp

Index: cc/CCLayerTreeHost.cpp
diff --git a/cc/CCLayerTreeHost.cpp b/cc/CCLayerTreeHost.cpp
index 10dcda8abb3e6ff8257adbf4011f6a0c462c5212..902ad95fdcafedda46de7bbe9191028846d049d3 100644
--- a/cc/CCLayerTreeHost.cpp
+++ b/cc/CCLayerTreeHost.cpp
@@ -405,6 +405,13 @@ void CCLayerTreeHost::reduceContentsTexturesMemoryOnImplThread(size_t limitBytes
     m_contentsTextureManager->reduceMemoryOnImplThread(limitBytes, resourceProvider);
 }
 
+bool CCLayerTreeHost::evictedContentsTexturesBackingsExist() const
+{
+    ASSERT(CCProxy::isImplThread());
+    ASSERT(m_contentsTextureManager.get());
+    return m_contentsTextureManager->evictedBackingsExist();
+}
+
 void CCLayerTreeHost::getEvictedContentTexturesBackings(CCPrioritizedTextureManager::BackingVector& evictedBackings)
 {
     ASSERT(CCProxy::isImplThread());