LTHI does not treat 0 as a valid time tick, instead it

will use gfx::FrameTime::Now().

Start frame time ticks at 1 millisecond so that LTHI does not use gfx::FrameTime::Now().

BUG=

Review URL: https://codereview.chromium.org/438373002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@287641 0039d316-1c4b-4281-b951-d872f2087c98

cc/layers/picture_layer_impl_unittest.cc

@@ -406,6 +406,7 @@ TEST_F(PictureLayerImplTest, ExternalViewportRectForPrioritizingTiles) {
 
 TEST_F(PictureLayerImplTest, InvalidViewportForPrioritizingTiles) {
   base::TimeTicks time_ticks;
+  time_ticks += base::TimeDelta::FromMilliseconds(1);
   host_impl_.SetCurrentFrameTimeTicks(time_ticks);
 
   gfx::Size tile_size(100, 100);
@@ -494,6 +495,7 @@ TEST_F(PictureLayerImplTest, InvalidViewportForPrioritizingTiles) {
 
 TEST_F(PictureLayerImplTest, InvalidViewportAfterReleaseResources) {
   base::TimeTicks time_ticks;
+  time_ticks += base::TimeDelta::FromMilliseconds(1);
   host_impl_.SetCurrentFrameTimeTicks(time_ticks);
 
   gfx::Size tile_size(100, 100);
@@ -2674,6 +2676,7 @@ TEST_F(NoLowResPictureLayerImplTest, NothingRequiredIfActiveMissingTiles) {
 
 TEST_F(NoLowResPictureLayerImplTest, InvalidViewportForPrioritizingTiles) {
   base::TimeTicks time_ticks;
+  time_ticks += base::TimeDelta::FromMilliseconds(1);
   host_impl_.SetCurrentFrameTimeTicks(time_ticks);
 
   gfx::Size tile_size(100, 100);
@@ -2762,6 +2765,7 @@ TEST_F(NoLowResPictureLayerImplTest, InvalidViewportForPrioritizingTiles) {
 
 TEST_F(NoLowResPictureLayerImplTest, InvalidViewportAfterReleaseResources) {
   base::TimeTicks time_ticks;
+  time_ticks += base::TimeDelta::FromMilliseconds(1);
   host_impl_.SetCurrentFrameTimeTicks(time_ticks);
 
   gfx::Size tile_size(100, 100);