My clang now doesn't complain about !"foo".

src/doc/SkDocument.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkDocument.h"
 #include "SkStream.h"
 
@@ skipping 31 matching lines @@
             case kBetweenPages_State:
                 fState = kInPage_State;
                 return this->onBeginPage(width, height, inner);
             case kInPage_State:
                 this->endPage();
                 break;
             case kClosed_State:
                 return NULL;
         }
     }
-    SkASSERT(!"never get here");
+    SkDEBUGFAIL("never get here");
     return NULL;
 }
 
 void SkDocument::endPage() {
     if (kInPage_State == fState) {
         fState = kBetweenPages_State;
         this->onEndPage();
     }
 }
 
@@ skipping 12 matching lines @@
                 fStream = NULL;
                 return;
             case kInPage_State:
                 this->endPage();
                 break;
             case kClosed_State:
                 return;
         }
     }
 }