Oilpan: build fix after r177435

Source/core/html/canvas/WebGLRenderingContextBase.cpp

Index: Source/core/html/canvas/WebGLRenderingContextBase.cpp
diff --git a/Source/core/html/canvas/WebGLRenderingContextBase.cpp b/Source/core/html/canvas/WebGLRenderingContextBase.cpp
index 7ee822f68eb98575b0917ed32f998c5a4400ad81..a52eb64d68173acf513ef3209fef55b7db695da7 100644
--- a/Source/core/html/canvas/WebGLRenderingContextBase.cpp
+++ b/Source/core/html/canvas/WebGLRenderingContextBase.cpp
@@ -116,7 +116,7 @@ void WebGLRenderingContextBase::forciblyLoseOldestContext(const String& reason)
     // been lost. Garbage collection might be triggered in the middle of this function, for
     // example, printWarningToConsole() causes an upcall to JavaScript.
     // Must make sure that the context is not deleted until the call stack unwinds.
-    RefPtr<WebGLRenderingContextBase> protect(candidate);
+    RefPtrWillBeRawPtr<WebGLRenderingContextBase> protect(candidate);
 
     activeContexts().remove(candidateID);