Fix scrolling on sites that use <frame>s

Update the dimensions of a frame before expanding it to fit the content
width and height.

Also, force a relayout of the frame as necessary to sync the correct
dimensions (i.e. when navigation occurs inside the frame)

Bug: 5978268
Change-Id: Ia282d6e5753fd38b32854e01ca58fa41b3814b21

2 files changed, 17 insertions, 4 deletions

diff --git a/Source/WebCore/page/FrameView.cpp b/Source/WebCore/page/FrameView.cpp
index f332074..8f2958c 100644
--- a/Source/WebCore/page/FrameView.cpp
+++ b/Source/WebCore/page/FrameView.cpp
@@ -1745,6 +1745,11 @@ void FrameView::scheduleRelayout()
             m_frame->ownerRenderer()->setNeedsLayout(true, true);
     }
 
+#ifdef ANDROID_FLATTEN_FRAMESET
+    if (m_frame->ownerRenderer() && m_frame->ownerElement()->hasTagName(frameTag))
+        m_frame->ownerRenderer()->setNeedsLayoutAndPrefWidthsRecalc();
+#endif
+
     int delay = m_frame->document()->minimumLayoutDelay();
     if (m_layoutTimer.isActive() && m_delayedLayout && !delay)
         unscheduleRelayout();
diff --git a/Source/WebCore/rendering/RenderFrame.cpp b/Source/WebCore/rendering/RenderFrame.cpp
index 4b1444b..0ae6eda 100644
--- a/Source/WebCore/rendering/RenderFrame.cpp
+++ b/Source/WebCore/rendering/RenderFrame.cpp
@@ -64,7 +64,12 @@ void RenderFrame::layout()
 {
     FrameView* view = static_cast<FrameView*>(widget());
     RenderView* root = view ? view->frame()->contentRenderer() : 0;
+
+    // Do not expand frames which has zero width or height
     if (!width() || !height() || !root) {
+        updateWidgetPosition();
+        if (view)
+            view->layout();
         setNeedsLayout(false);
         return;
     }
@@ -75,14 +80,17 @@ void RenderFrame::layout()
         return;
     }
 
-    int layoutWidth = width();
+    // Update the dimensions to get the correct width and height
+    updateWidgetPosition();
+    if (root->preferredLogicalWidthsDirty())
+        root->computePreferredLogicalWidths();
 
+    // Expand the frame by setting frame height = content height
     setWidth(max(view->contentsWidth() + borderAndPaddingWidth(), width()));
     setHeight(max(view->contentsHeight() + borderAndPaddingHeight(), height()));
 
-    // Trigger a layout of the FrameView which will schedule a relayout of this RenderFrame.
-    if (layoutWidth < width())
-        view->layout();
+    // Update one more time
+    updateWidgetPosition();
 
     setNeedsLayout(false);
 }