Deferred frame loading stats v2

third_party/WebKit/Source/core/frame/FrameView.cpp

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index e8b7ec1112d4094ad011ab24af71a31b7b1fef2f..8dda919717d2da5089824fb8bb191852119af575 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -4395,11 +4395,26 @@ void FrameView::updateViewportIntersectionIfNeeded() {
   m_viewportIntersectionValid = true;
   FrameView* parent = parentFrameView();
   if (!parent) {
+    if (HTMLFrameOwnerElement* element = frame().deprecatedLocalOwner()) {
+      if (!element->layoutObject())
+        frame().document()->wouldLoadBecause(WouldLoadDisplayNone);
+    }
+    frame().document()->wouldLoadBecause(WouldLoadOutOfProcess);

[dcheng, 2016/10/08 00:46:22]

Should this be in an else?

[dgrogan, 2016/10/13 01:06:22]

It was ok without one because of the check in Document::wouldLoadBecause that
only records to UMA on the first call. But it's clearer with the "else" so
changed.

     m_viewportIntersection = frameRect();
     return;
   }
   ASSERT(!parent->m_needsUpdateViewportIntersection);
 
+  bool parentLoaded = parent->frame().document()->wouldLoadReason() != Created;

[dcheng, 2016/10/08 00:46:22]

Maybe add a comment here: it'll help me understand why we care about the parent
frame's load reason being something other than created. I guess it's because we
want to only "chain" down the reasons once the parent frame has proceeded past
the Created state, but an explicit comment to that effect might be good.

[dgrogan, 2016/10/13 01:06:22]

Comment added. I think we're saying the same thing but let me know if it's still
not clear. Also, changed the != to > for easier understanding.

+  if (parentLoaded) {
+    if (frameRect().isEmpty())
+      frame().document()->wouldLoadBecause(WouldLoadZeroByZero);
+    else if (frameRect().maxY() < 0)
+      frame().document()->wouldLoadBecause(WouldLoadAbove);
+    else if (frameRect().maxX() < 0)
+      frame().document()->wouldLoadBecause(WouldLoadLeft);
+  }
+
   // If our parent is hidden, then we are too.
   if (parent->m_viewportIntersection.isEmpty()) {
     m_viewportIntersection = parent->m_viewportIntersection;
@@ -4419,6 +4434,9 @@ void FrameView::updateViewportIntersectionIfNeeded() {
   // content while scrolling.
   IntRect viewport = parent->m_viewportIntersection;
   m_viewportIntersection.intersect(viewport);
+
+  if (parentLoaded && !m_viewportIntersection.isEmpty())
+    frame().document()->wouldLoadBecause(WouldLoadVisible);
 }
 
 void FrameView::updateViewportIntersectionsForSubtree(
@@ -4504,8 +4522,6 @@ void FrameView::notifyRenderThrottlingObservers() {
 
   updateThrottlingStatus();
 
-  frame().document()->onVisibilityMaybeChanged(!m_hiddenForThrottling);
-
   bool becameThrottled = !wasThrottled && canThrottleRendering();
   bool becameUnthrottled = wasThrottled && !canThrottleRendering();
   ScrollingCoordinator* scrollingCoordinator = this->scrollingCoordinator();