Introduce painted-device-scale-factor and use it when --enable-use-zoom-for-dsf is specified.

cc/trees/layer_tree_host_unittest.cc

Index: cc/trees/layer_tree_host_unittest.cc
diff --git a/cc/trees/layer_tree_host_unittest.cc b/cc/trees/layer_tree_host_unittest.cc
index e75b3e9a2ba4a0324fee2176942bc83c2080f5a7..afe7b99021fa66d78050dfe7cc3076c2665754a1 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -35,6 +35,7 @@
 #include "cc/test/fake_display_list_recording_source.h"
 #include "cc/test/fake_layer_tree_host_client.h"
 #include "cc/test/fake_output_surface.h"
+#include "cc/test/fake_output_surface_client.h"

[danakj, 2015/10/24 00:08:07]

not needed?

[oshima, 2015/10/27 20:28:09]

Done.

 #include "cc/test/fake_painted_scrollbar_layer.h"
 #include "cc/test/fake_picture_layer.h"
 #include "cc/test/fake_picture_layer_impl.h"
@@ -6378,5 +6379,28 @@ class LayerTreeHostTestDestroyWhileInitializingOutputSurface
 
 MULTI_THREAD_TEST_F(LayerTreeHostTestDestroyWhileInitializingOutputSurface);
 
+// Makes sure that painted_device_scale_factor is propagated to the
+// frame's metadata.
+class LayerTreeHostTestPaintedDeviceScaleFactor : public LayerTreeHostTest {
+ protected:
+  void BeginTest() override {
+    layer_tree_host()->SetPaintedDeviceScaleFactor(2.0f);
+    EXPECT_EQ(1.0f, layer_tree_host()->device_scale_factor());
+    PostSetNeedsCommitToMainThread();
+  }
+
+  void SwapBuffersOnThread(LayerTreeHostImpl* host_impl, bool result) override {
+    EXPECT_EQ(2.0f,

[danakj, 2015/10/24 00:07:00]

Great, thanks. The cc parts LGTM

+              output_surface()->last_sent_frame().metadata.device_scale_factor);
+    EXPECT_EQ(2.0f, host_impl->active_tree()->painted_device_scale_factor());
+    EXPECT_EQ(1.0f, host_impl->active_tree()->device_scale_factor());
+    EndTest();
+  }
+
+  void AfterTest() override {}
+};
+
+MULTI_THREAD_TEST_F(LayerTreeHostTestPaintedDeviceScaleFactor);

[danakj, 2015/10/24 00:08:07]

Why is it MULTI only and not SINGLE_AND_MULTI?

[oshima, 2015/10/27 20:28:09]

Done.

+
 }  // namespace
 }  // namespace cc