gpu: Add ARB_occlusion_query support.

gpu/command_buffer/client/gles2_implementation.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // A class to emulate GLES2 over command buffers.
 
 #include "gpu/command_buffer/client/gles2_implementation.h"
 
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>
@@ skipping 5532 matching lines @@
     case GL_GET_ERROR_QUERY_CHROMIUM:
       break;
     case GL_COMMANDS_COMPLETED_CHROMIUM:
       if (!capabilities_.sync_query) {
         SetGLError(
             GL_INVALID_OPERATION, "glBeginQueryEXT",
             "not enabled for commands completed queries");
         return;
       }
       break;
+    case GL_SAMPLES_PASSED_ARB:
+      if (!capabilities_.occlusion_query) {
+        SetGLError(
+            GL_INVALID_OPERATION, "glBeginQueryEXT",
+            "not enabled for occlusion queries");
+        return;
+      }
+      break;
     case GL_ANY_SAMPLES_PASSED:
     case GL_ANY_SAMPLES_PASSED_CONSERVATIVE:
       if (!capabilities_.occlusion_query_boolean) {
         SetGLError(
             GL_INVALID_OPERATION, "glBeginQueryEXT",
-            "not enabled for occlusion queries");
+            "not enabled for boolean occlusion queries");
         return;
       }
       break;
     case GL_TIME_ELAPSED_EXT:
       if (!capabilities_.timer_queries) {
         SetGLError(
             GL_INVALID_OPERATION, "glBeginQueryEXT",
             "not enabled for timing queries");
         return;
       }
@@ skipping 1503 matching lines @@
   CheckGLError();
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/client/gles2_implementation_impl_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu