Bug 1115691 patch 1 - Store counts of frames constructed and reflowed on the pres context. r=roc

(I've tested the frame construction counts in my test for bug 1110277; I
haven't actually tested the reflow counts.)

layout/base/nsPresContext.h

@@ -821,6 +821,20 @@ public:
                                 nsIFrame * aFrame);
 #endif
 
+  void ConstructedFrame() {
+    ++mFramesConstructed;
+  }
+  void ReflowedFrame() {
+    ++mFramesReflowed;
+  }
+
+  uint64_t FramesConstructedCount() {
+    return mFramesConstructed;
+  }
+  uint64_t FramesReflowedCount() {
+    return mFramesReflowed;
+  }
+
   /**
    * This table maps border-width enums 'thin', 'medium', 'thick'
    * to actual nscoord values.
@@ -1289,6 +1303,11 @@ protected:
 
   uint32_t              mInterruptChecksToSkip;
 
+  // Counters for tests and tools that want to detect frame construction
+  // or reflow.
+  uint64_t              mFramesConstructed;
+  uint64_t              mFramesReflowed;
+
   mozilla::TimeStamp    mReflowStartTime;
 
   // last time we did a full style flush

layout/generic/nsFrame.cpp

@@ -538,6 +538,8 @@ nsFrame::Init(nsIContent*       aContent,
                        NS_FRAME_MAY_BE_TRANSFORMED |
                        NS_FRAME_MAY_HAVE_GENERATED_CONTENT |
                        NS_FRAME_CAN_HAVE_ABSPOS_CHILDREN);
+  } else {
+    PresContext()->ConstructedFrame();
   }
   if (GetParent()) {
     nsFrameState state = GetParent()->GetStateBits();
@@ -4432,6 +4434,8 @@ nsFrame::DidReflow(nsPresContext*           aPresContext,
       aReflowState->mPercentHeightObserver->NotifyPercentHeight(*aReflowState);
     }
   }
+
+  aPresContext->ReflowedFrame();
 }
 
 void