Added Blink-side support for EXT_blend_minmax WebGL extension

Source/core/html/canvas/EXTBlendMinMax.cpp

Index: Source/core/html/canvas/EXTBlendMinMax.cpp
diff --git a/Source/core/html/canvas/EXTBlendMinMax.cpp b/Source/core/html/canvas/EXTBlendMinMax.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..8ded7388912e5813440cdd17a0747b97c75557b0
--- /dev/null
+++ b/Source/core/html/canvas/EXTBlendMinMax.cpp
@@ -0,0 +1,42 @@
+// Copyright 2014 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 "config.h"
+
+#include "core/html/canvas/EXTBlendMinMax.h"
+
+namespace WebCore {
+
+EXTBlendMinMax::EXTBlendMinMax(WebGLRenderingContextBase* context)
+    : WebGLExtension(context)
+{
+    ScriptWrappable::init(this);
+    context->extensionsUtil()->ensureExtensionEnabled("GL_EXT_blend_minmax");
+}
+
+EXTBlendMinMax::~EXTBlendMinMax()
+{
+}
+
+WebGLExtensionName EXTBlendMinMax::name() const
+{
+    return EXTBlendMinMaxName;
+}
+
+PassRefPtr<EXTBlendMinMax> EXTBlendMinMax::create(WebGLRenderingContextBase* context)
+{
+    return adoptRef(new EXTBlendMinMax(context));
+}
+
+bool EXTBlendMinMax::supported(WebGLRenderingContextBase* context)
+{
+    return context->extensionsUtil()->supportsExtension("GL_EXT_blend_minmax");
+}
+
+const char* EXTBlendMinMax::extensionName()
+{
+    return "EXT_blend_minmax";
+}
+
+} // namespace WebCore