bug 522779: use nsTArray::Contains() instead of checking nsTArray::IndexOf() against various sentinel values, in three places in layout. r=dbaron

layout/base/nsCSSFrameConstructor.cpp

@@ -6973,7 +6973,7 @@ DoDeletingFrameSubtree(nsFrameManager*      aFrameManager,
         // the out-of-flow frame will be destroyed by aRemovedFrame.
         if (outOfFlowFrame->GetStyleDisplay()->mDisplay == NS_STYLE_DISPLAY_POPUP ||
             !nsLayoutUtils::IsProperAncestorFrame(aRemovedFrame, outOfFlowFrame)) {
-          NS_ASSERTION(aDestroyQueue.IndexOf(outOfFlowFrame) == kNotFound,
+          NS_ASSERTION(!aDestroyQueue.Contains(outOfFlowFrame),
                        "out-of-flow is already in the destroy queue");
           aDestroyQueue.AppendElement(outOfFlowFrame);
           // Recurse into the out-of-flow, it is now the aRemovedFrame.

layout/generic/nsImageFrame.h

@@ -314,8 +314,7 @@ private:
     NS_DECL_IMGIDECODEROBSERVER
 
     void AddIconObserver(nsImageFrame *frame) {
-        NS_ABORT_IF_FALSE(mIconObservers.IndexOf(frame) ==
-                          nsTArray<nsImageFrame*>::NoIndex,
+        NS_ABORT_IF_FALSE(!mIconObservers.Contains(frame),
                           "Observer shouldn't aleady be in array");
         mIconObservers.AppendElement(frame);
     }

layout/mathml/nsMathMLChar.cpp

@@ -1527,7 +1527,7 @@ nsMathMLChar::StretchEnumContext::EnumCallback(const nsString& aFamily,
   nsGlyphTable* glyphTable = aGeneric ?
     &gGlyphTableList->mUnicodeTable : gGlyphTableList->GetGlyphTableFor(aFamily);
 
-  if (context->mTablesTried.IndexOf(glyphTable) != context->mTablesTried.NoIndex)
+  if (context->mTablesTried.Contains(glyphTable))
     return PR_TRUE; // already tried this one
 
   context->mGlyphTable = glyphTable;