Completely removed the Extensions3D class (Take 2)

Source/core/html/canvas/OESTextureFloatLinear.cpp

Index: Source/core/html/canvas/OESTextureFloatLinear.cpp
diff --git a/Source/core/html/canvas/OESTextureFloatLinear.cpp b/Source/core/html/canvas/OESTextureFloatLinear.cpp
index 1e8518d95d66fad953c565ba1b1a98642df71fa8..4ed8c7123e4903d203a521dabc013b906af81793 100644
--- a/Source/core/html/canvas/OESTextureFloatLinear.cpp
+++ b/Source/core/html/canvas/OESTextureFloatLinear.cpp
@@ -27,15 +27,13 @@
 
 #include "core/html/canvas/OESTextureFloatLinear.h"
 
-#include "platform/graphics/Extensions3D.h"
-
 namespace WebCore {
 
 OESTextureFloatLinear::OESTextureFloatLinear(WebGLRenderingContext* context)
     : WebGLExtension(context)
 {
     ScriptWrappable::init(this);
-    context->graphicsContext3D()->extensions()->ensureEnabled("GL_OES_texture_float_linear");
+    context->graphicsContext3D()->ensureExtensionEnabled("GL_OES_texture_float_linear");
 }
 
 OESTextureFloatLinear::~OESTextureFloatLinear()
@@ -54,8 +52,7 @@ PassRefPtr<OESTextureFloatLinear> OESTextureFloatLinear::create(WebGLRenderingCo
 
 bool OESTextureFloatLinear::supported(WebGLRenderingContext* context)
 {
-    Extensions3D* extensions = context->graphicsContext3D()->extensions();
-    return extensions->supports("GL_OES_texture_float_linear");
+    return context->graphicsContext3D()->supportsExtension("GL_OES_texture_float_linear");
 }
 
 const char* OESTextureFloatLinear::extensionName()