Bug 957021 - Fix messed-up memory reporter paths. r=khuey.

--HG--
extra : rebase_source : 2bd46a9442c54ffba04279a405aeb270ce7bbb23

dom/base/nsWindowMemoryReporter.cpp

@@ -181,7 +181,7 @@ CollectWindowReports(nsGlobalWindow *aWindow,
                      nsIMemoryReporterCallback *aCb,
                      nsISupports *aClosure)
 {
-  nsAutoCString windowPath;
+  nsAutoCString windowPath("explicit/");
 
   // Avoid calling aWindow->GetTop() if there's no outer window.  It will work
   // just fine, but will spew a lot of warnings.
@@ -233,20 +233,17 @@ CollectWindowReports(nsGlobalWindow *aWindow,
   AppendWindowURI(aWindow, windowPath);
   windowPath += NS_LITERAL_CSTRING(")");
 
-  nsCString explicitWindowPath("explicit/");
-  explicitWindowPath += windowPath;
-
-  // XXXkhuey 
-  nsCString censusWindowPath("event-counts/");
-  censusWindowPath += windowPath;
+  // Use |windowPath|, but replace "explicit/" with "event-counts/".
+  nsCString censusWindowPath(windowPath);
+  censusWindowPath.Replace(0, strlen("explicit"), "event-counts");
 
   // Remember the path for later.
-  aWindowPaths->Put(aWindow->WindowID(), explicitWindowPath);
+  aWindowPaths->Put(aWindow->WindowID(), windowPath);
 
 #define REPORT_SIZE(_pathTail, _amount, _desc)                                \
   do {                                                                        \
     if (_amount > 0) {                                                        \
-      nsAutoCString path(explicitWindowPath);                                 \
+      nsAutoCString path(windowPath);                                         \
       path += _pathTail;                                                      \
       nsresult rv;                                                            \
       rv = aCb->Callback(EmptyCString(), path, nsIMemoryReporter::KIND_HEAP,  \

js/xpconnect/src/XPCJSRuntime.cpp

@@ -2450,6 +2450,15 @@ class OrphanReporter : public JS::ObjectPrivateVisitor
     nsTHashtable <nsISupportsHashKey> mAlreadyMeasuredOrphanTrees;
 };
 
+#ifdef DEBUG
+static bool
+StartsWithExplicit(nsACString& s)
+{
+    const char* e = "explicit/";
+    return Substring(s, 0, strlen(e)).Equals(e);
+}
+#endif
+
 class XPCJSRuntimeStats : public JS::RuntimeStats
 {
     WindowPaths *mWindowPaths;
@@ -2498,6 +2507,8 @@ class XPCJSRuntimeStats : public JS::RuntimeStats
 
         extras->pathPrefix += nsPrintfCString("zone(0x%p)/", (void *)zone);
 
+        MOZ_ASSERT(StartsWithExplicit(extras->pathPrefix));
+
         zStats->extra = extras;
     }
 
@@ -2566,6 +2577,9 @@ class XPCJSRuntimeStats : public JS::RuntimeStats
         // be used, because non-nsGlobalWindow compartments shouldn't have
         // orphan DOM nodes).
 
+        MOZ_ASSERT(StartsWithExplicit(extras->jsPathPrefix));
+        MOZ_ASSERT(StartsWithExplicit(extras->domPathPrefix));
+
         cstats->extra = extras;
     }
 };