Added support for EXTDisjointTimerQuery on the Blink side.

Source/modules/webgl/WebGLTimerQueryEXT.h

Index: Source/modules/webgl/WebGLTimerQueryEXT.h
diff --git a/Source/modules/webgl/WebGLTimerQueryEXT.h b/Source/modules/webgl/WebGLTimerQueryEXT.h
new file mode 100644
index 0000000000000000000000000000000000000000..feef5be1b762a0e0fed1524fa9e5410604b836a6
--- /dev/null
+++ b/Source/modules/webgl/WebGLTimerQueryEXT.h
@@ -0,0 +1,38 @@
+// 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.
+
+#ifndef WebGLTimerQueryEXT_h
+#define WebGLTimerQueryEXT_h
+
+#include "modules/webgl/WebGLContextObject.h"
+
+namespace blink {
+
+class WebGLTimerQueryEXT : public WebGLContextObject {
+    DEFINE_WRAPPERTYPEINFO();
+
+public:
+    static WebGLTimerQueryEXT* create(WebGLRenderingContextBase*);
+    ~WebGLTimerQueryEXT() override;
+
+    void setTarget(GLenum target) { m_target = target; }
+
+    GLuint object() const { return m_queryId; }
+    bool hasTarget() const { return m_target != 0; }
+    GLenum target() const { return m_target; }
+
+protected:
+    WebGLTimerQueryEXT(WebGLRenderingContextBase*);
+
+private:
+    bool hasObject() const override { return m_queryId != 0; }
+    void deleteObjectImpl(WebGraphicsContext3D*) override;
+
+    GLenum m_target;
+    GLuint m_queryId;
+};
+
+} // namespace blink
+
+#endif // WebGLTimerQueryEXT_h