gpu: support immutable texture on Linux Mesa driver and GLES3.

gpu/command_buffer/service/feature_info.cc

Index: gpu/command_buffer/service/feature_info.cc
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index e58e6c21fc7b0afaa76c230f716566c9907120cf..f61385c483802f251b659a82c154446870506069 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -691,7 +691,8 @@ void FeatureInfo::InitializeFeatures() {
     validators_.texture_parameter.AddValue(GL_TEXTURE_USAGE_ANGLE);
   }
 
-  if (extensions.Contains("GL_EXT_texture_storage")) {
+  if (extensions.Contains("GL_EXT_texture_storage") ||

[bsalomon, 2014/08/19 13:28:44]

Shouldn't there also be an is_es3 check here?

+      extensions.Contains("GL_ARB_texture_storage")) {
     feature_flags_.ext_texture_storage = true;
     AddExtensionString("GL_EXT_texture_storage");
     validators_.texture_parameter.AddValue(GL_TEXTURE_IMMUTABLE_FORMAT_EXT);