use layer id to maintain selection

The pictures used to draw the page content can change
in response to refreshes, as the selection is moved or
as the screen is scrolled or zoomed.

Track the layer id, instead of the picture pointer,
to find the picture that contains the current selection.

Before, the selection would disappear as the screen
was pinched, or the highlight might disappear even
though the anchors draw, or the highlight and anchors
might be drawn offset from the screen data. This change
eliminates this class of bugs.

Change-Id: Ifc440b8aa0c9d6d232e298e42c4c544a41629442
http://b/3183492

1 files changed, 1 insertions, 0 deletions

diff --git a/WebKit/android/nav/SelectText.h b/WebKit/android/nav/SelectText.h
index d210117..8247356 100644
--- a/WebKit/android/nav/SelectText.h
+++ b/WebKit/android/nav/SelectText.h
@@ -73,6 +73,7 @@ private:
     SkIRect m_selEnd;
     int m_startBase;
     int m_endBase;
+    int m_layerId;
     SkIRect m_visibleRect; // constrains picture computations to visible area
     SkRegion m_selRegion; // computed from sel start, end
     SkPicture m_startControl;