cc: Enable GL_RED_EXT for YUV resources

cc/resources/resource_provider.cc

Index: cc/resources/resource_provider.cc
diff --git a/cc/resources/resource_provider.cc b/cc/resources/resource_provider.cc
index 04351e12e6ab6e76ec3c67fdd8962040dd8a6b14..fe7cc003ddf1c76bc5dc56849122e2e27e07bcdb 100644
--- a/cc/resources/resource_provider.cc
+++ b/cc/resources/resource_provider.cc
@@ -1219,6 +1219,7 @@ ResourceProvider::ResourceProvider(
       use_texture_format_bgra_(false),
       use_texture_usage_hint_(false),
       use_compressed_texture_etc1_(false),
+      yuv_resource_format_(LUMINANCE_8),
       max_texture_size_(0),
       best_texture_format_(RGBA_8888),
       use_rgba_4444_texture_format_(use_rgba_4444_texture_format),
@@ -1257,6 +1258,7 @@ void ResourceProvider::InitializeGL() {
   use_texture_format_bgra_ = caps.gpu.texture_format_bgra8888;
   use_texture_usage_hint_ = caps.gpu.texture_usage;
   use_compressed_texture_etc1_ = caps.gpu.texture_format_etc1;
+  yuv_resource_format_ = caps.gpu.texture_rg ? RED_8 : LUMINANCE_8;
   use_sync_query_ = caps.gpu.sync_query;
 
   GLES2Interface* gl = ContextGL();