cc: Don't let invalidations that we're going to handle immediately cause an extra commit.

cc/layer_tree_host_unittest.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layer_tree_host.h"
 
 #include "base/synchronization/lock.h"
 #include "cc/content_layer.h"
 #include "cc/content_layer_client.h"
 #include "cc/layer_impl.h"
@@ skipping 260 matching lines @@
 private:
     int m_numCommits;
     int m_numDraws;
 };
 
 TEST_F(LayerTreeHostTestSetNeedsRedraw, runMultiThread)
 {
     runTest(true);
 }
 
+class LayerTreeHostTestNoExtraCommitFromInvalidate : public LayerTreeHostTest {
+public:
+    LayerTreeHostTestNoExtraCommitFromInvalidate()
+        : m_rootLayer(ContentLayer::create(&m_client))
+    {
+    }
+
+    virtual void beginTest() OVERRIDE
+    {
+        m_rootLayer->setAutomaticallyComputeRasterScale(false);
+        m_rootLayer->setIsDrawable(true);
+        m_rootLayer->setBounds(gfx::Size(1, 1));
+        m_layerTreeHost->setRootLayer(m_rootLayer);
+        postSetNeedsCommitToMainThread();
+    }
+
+    virtual void didCommit() OVERRIDE
+    {
+        switch (m_layerTreeHost->commitNumber()) {
+        case 1:
+            // Changing the content bounds will cause a single commit!
+            m_rootLayer->setRasterScale(4.0f);
+            break;
+        default:
+            // No extra commits.
+            EXPECT_EQ(2, m_layerTreeHost->commitNumber());
+            endTest();
+        }
+    }
+
+    virtual void afterTest() OVERRIDE
+    {
+    }
+
+private:
+    FakeContentLayerClient m_client;
+    scoped_refptr<ContentLayer> m_rootLayer;
+};
+
+SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestNoExtraCommitFromInvalidate)
+
 class LayerTreeHostTestCompositeAndReadback : public LayerTreeHostTest {
 public:
     LayerTreeHostTestCompositeAndReadback()
         : m_numCommits(0)
     {
     }
 
     virtual void beginTest() OVERRIDE
     {
         postSetNeedsCommitToMainThread();
@@ skipping 2668 matching lines @@
     LayerTreeSettings settings;
     settings.maxPartialTextureUpdates = 4;
 
     scoped_ptr<LayerTreeHost> host = LayerTreeHost::create(&client, settings, scoped_ptr<Thread>());
     EXPECT_TRUE(host->initializeRendererIfNeeded());
     EXPECT_EQ(0u, host->settings().maxPartialTextureUpdates);
 }
 
 }  // namespace
 }  // namespace cc