cc: Adding support for RGBA_4444 tile textures

cc/base/switches.cc

Index: cc/base/switches.cc
diff --git a/cc/base/switches.cc b/cc/base/switches.cc
index 3fc43029c266cd1666695f7a90dc110953523bf7..22f97603857ceb4c665de9c82d19c4327612b234 100644
--- a/cc/base/switches.cc
+++ b/cc/base/switches.cc
@@ -135,6 +135,9 @@ const char kDisableMapImage[] = "disable-map-image";
 // Prevents the layer tree unit tests from timing out.
 const char kCCLayerTreeTestNoTimeout[] = "cc-layer-tree-test-no-timeout";
 
+// Disable textures using RGBA_4444 layout.
+const char kDisable4444Textures[] = "disable-4444-textures";
+
 bool IsImplSidePaintingEnabled() {
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();