Implement EXT_disjoint_timer_query_webgl2

third_party/WebKit/Source/modules/webgl/EXTDisjointTimerQuery.cpp

 // Copyright 2015 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.
 
 #include "modules/webgl/EXTDisjointTimerQuery.h"
 
 #include "bindings/modules/v8/WebGLAny.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "modules/webgl/WebGLRenderingContextBase.h"
 #include "modules/webgl/WebGLTimerQueryEXT.h"
@@ skipping 64 matching lines @@
   }
 
   if (target != GL_TIME_ELAPSED_EXT) {
     scoped.context()->synthesizeGLError(GL_INVALID_ENUM, "beginQueryEXT",
                                         "invalid target");
     return;
   }
 
   if (m_currentElapsedQuery) {
     scoped.context()->synthesizeGLError(GL_INVALID_OPERATION, "beginQueryEXT",
-                                        "no current query");
+                                        "a query is already active for target");
     return;
   }
 
   if (query->hasTarget() && query->target() != target) {
     scoped.context()->synthesizeGLError(GL_INVALID_OPERATION, "beginQueryEXT",
                                         "target does not match query");
     return;
   }
 
   scoped.context()->contextGL()->BeginQueryEXT(target, query->object());
@@ skipping 118 matching lines @@
   WebGLExtension::trace(visitor);
 }
 
 EXTDisjointTimerQuery::EXTDisjointTimerQuery(WebGLRenderingContextBase* context)
     : WebGLExtension(context) {
   context->extensionsUtil()->ensureExtensionEnabled(
       "GL_EXT_disjoint_timer_query");
 }
 
 }  // namespace blink