Allow one-copy task tile worker pool to use compressed textures.

cc/output/renderer_settings.cc

Index: cc/output/renderer_settings.cc
diff --git a/cc/output/renderer_settings.cc b/cc/output/renderer_settings.cc
index 7b182784035baf443db0c6608b85a068c8dea35c..a555b0b8cd0ea5ee453696e4b671c2f9c06eff08 100644
--- a/cc/output/renderer_settings.cc
+++ b/cc/output/renderer_settings.cc
@@ -7,6 +7,7 @@
 #include <limits>
 
 #include "base/logging.h"
+#include "cc/resources/platform_color.h"
 
 namespace cc {
 
@@ -21,9 +22,9 @@ RendererSettings::RendererSettings()
       delay_releasing_overlay_resources(false),
       refresh_rate(60.0),
       highp_threshold_min(0),
-      use_rgba_4444_textures(false),
       texture_id_allocation_chunk_size(64),
-      use_gpu_memory_buffer_resources(false) {}
+      use_gpu_memory_buffer_resources(false),
+      preferred_tile_format(PlatformColor::BestTextureFormat()) {}
 
 RendererSettings::~RendererSettings() {
 }