Moved the majority of WebGL functionality into WebGLRenderingContextBase

Source/core/html/canvas/OESTextureHalfFloat.cpp

Index: Source/core/html/canvas/OESTextureHalfFloat.cpp
diff --git a/Source/core/html/canvas/OESTextureHalfFloat.cpp b/Source/core/html/canvas/OESTextureHalfFloat.cpp
index 022e02a6c155595dfc73613989e904f4d9d2a8a9..f9bff1c328593952f08cb6e986f15ef7f250d533 100644
--- a/Source/core/html/canvas/OESTextureHalfFloat.cpp
+++ b/Source/core/html/canvas/OESTextureHalfFloat.cpp
@@ -30,7 +30,7 @@
 
 namespace WebCore {
 
-OESTextureHalfFloat::OESTextureHalfFloat(WebGLRenderingContext* context)
+OESTextureHalfFloat::OESTextureHalfFloat(WebGLRenderingContextBase* context)
     : WebGLExtension(context)
 {
     ScriptWrappable::init(this);
@@ -46,12 +46,12 @@ WebGLExtension::ExtensionName OESTextureHalfFloat::getName() const
     return OESTextureHalfFloatName;
 }
 
-PassRefPtr<OESTextureHalfFloat> OESTextureHalfFloat::create(WebGLRenderingContext* context)
+PassRefPtr<OESTextureHalfFloat> OESTextureHalfFloat::create(WebGLRenderingContextBase* context)
 {
     return adoptRef(new OESTextureHalfFloat(context));
 }
 
-bool OESTextureHalfFloat::supported(WebGLRenderingContext* context)
+bool OESTextureHalfFloat::supported(WebGLRenderingContextBase* context)
 {
     Extensions3D* extensions = context->graphicsContext3D()->getExtensions();
     return extensions->supports("GL_OES_texture_half_float");