Bug 939385 (part 3, attempt 2) - Expose vsizeMaxContiguous to about:memory. r=froydnj.

--HG--
extra : rebase_source : 2a7dcf2121c323bb37094b23e329c322f25dfeeb

toolkit/components/aboutmemory/tests/test_aboutmemory5.xul

@@ -104,7 +104,8 @@
         // If we have more than 1000 chars, we've probably successfully
         // copy+pasted.
         if (actual.length > 1000) {
-          let vsizes = actual.match(/vsize/g);
+          // Note: Match "vsize" but not "vsize-max-contiguous".
+          let vsizes = actual.match(/vsize[^-]/g);
           let endOfBrowsers  = actual.match(/End of Browser/g);
 
           if (vsizes.length == 4 && endOfBrowsers.length == 3) {

xpcom/base/nsMemoryReporterManager.cpp

@@ -400,6 +400,20 @@ static nsresult GetVsizeMaxContiguous(int64_t* aN)
     return NS_OK;
 }
 
+class VsizeMaxContiguousReporter MOZ_FINAL : public MemoryUniReporter
+{
+public:
+    VsizeMaxContiguousReporter()
+      : MemoryUniReporter("vsize-max-contiguous", KIND_OTHER, UNITS_BYTES,
+"Size of the maximum contiguous block of available virtual memory.")
+    {}
+
+    NS_IMETHOD GetAmount(int64_t* aAmount)
+    {
+        return GetVsizeMaxContiguous(aAmount);
+    }
+};
+
 #define HAVE_PRIVATE_REPORTER
 class PrivateReporter MOZ_FINAL : public MemoryUniReporter
 {
@@ -778,6 +792,10 @@ nsMemoryReporterManager::Init()
     RegisterReporter(new ResidentReporter);
 #endif
 
+#ifdef HAVE_VSIZE_MAX_CONTIGUOUS_REPORTER
+    RegisterReporter(new VsizeMaxContiguousReporter);
+#endif
+
 #ifdef HAVE_RESIDENT_UNIQUE_REPORTER
     RegisterReporter(new ResidentUniqueReporter);
 #endif