Rename WindowTreeHost G|SetBounds to indicate they are in pixels.

ash/shell_unittest.cc

Index: ash/shell_unittest.cc
diff --git a/ash/shell_unittest.cc b/ash/shell_unittest.cc
index db5d29cf35bcf4fc45ca521ca4fc4200d070740b..8e6f71a682851c149632e9418a577d4710003a76 100644
--- a/ash/shell_unittest.cc
+++ b/ash/shell_unittest.cc
@@ -375,8 +375,9 @@ TEST_F(ShellTest, ManagedWindowModeBasics) {
   EXPECT_TRUE(shelf_widget->IsVisible());
   // Shelf is at bottom-left of screen.
   EXPECT_EQ(0, shelf_widget->GetWindowBoundsInScreen().x());
-  EXPECT_EQ(Shell::GetPrimaryRootWindow()->GetHost()->GetBounds().height(),
-            shelf_widget->GetWindowBoundsInScreen().bottom());
+  EXPECT_EQ(
+      Shell::GetPrimaryRootWindow()->GetHost()->GetBoundsInPixel().height(),
+      shelf_widget->GetWindowBoundsInScreen().bottom());
   // We have a wallpaper but not a bare layer.
   // TODO (antrim): enable once we find out why it fails component build.
   //  WallpaperWidgetController* wallpaper =