Create errors (especially cancellation errors) internally to WebCore, rather

Source/core/loader/PolicyChecker.cpp

Index: Source/core/loader/PolicyChecker.cpp
===================================================================
--- Source/core/loader/PolicyChecker.cpp	(revision 148582)
+++ Source/core/loader/PolicyChecker.cpp	(working copy)
@@ -126,11 +126,6 @@
     callback.cancel();
 }
 
-void PolicyChecker::cannotShowMIMEType(const ResourceResponse& response)
-{
-    handleUnimplementablePolicy(m_frame->loader()->client()->cannotShowMIMETypeError(response));
-}
-
 void PolicyChecker::continueAfterNavigationPolicy(PolicyAction policy)
 {
     PolicyCallback callback = m_callback;
@@ -149,16 +144,8 @@
             callback.clearRequest();
             break;
         }
-        case PolicyUse: {
-            ResourceRequest request(callback.request());
-
-            if (!m_frame->loader()->client()->canHandleRequest(request)) {
-                handleUnimplementablePolicy(m_frame->loader()->client()->cannotShowURLError(callback.request()));
-                callback.clearRequest();
-                shouldContinue = false;
-            }
+        case PolicyUse:
             break;
-        }
     }
 
     callback.call(shouldContinue);
@@ -184,11 +171,4 @@
     callback.call(policy == PolicyUse);
 }
 
-void PolicyChecker::handleUnimplementablePolicy(const ResourceError& error)
-{
-    m_delegateIsHandlingUnimplementablePolicy = true;
-    m_frame->loader()->client()->dispatchUnableToImplementPolicy(error);
-    m_delegateIsHandlingUnimplementablePolicy = false;
-}
-
 } // namespace WebCore