Fix garbage showing up beneath dialogs

bug:17463894

Fixes the setViewport method to immediately affect the return values
of getViewportWidth/Height methods.

Also works around tiling extension issues observed on first frame
after window resize by disabling tiling for that frame.

Change-Id: Ie172d572d20d74a1be9cc58ad389af2cffa0e4b6

1 files changed, 7 insertions, 0 deletions

diff --git a/libs/hwui/StatefulBaseRenderer.cpp b/libs/hwui/StatefulBaseRenderer.cpp
index 12b8c8db28ea..88d6f6802909 100644
--- a/libs/hwui/StatefulBaseRenderer.cpp
+++ b/libs/hwui/StatefulBaseRenderer.cpp
@@ -49,6 +49,13 @@ void StatefulBaseRenderer::setViewport(int width, int height) {
     mHeight = height;
     mFirstSnapshot->initializeViewport(width, height);
     onViewportInitialized();
+
+    // create a temporary 1st snapshot, so old snapshots are released,
+    // and viewport can be queried safely.
+    // TODO: remove, combine viewport + save stack initialization
+    mSnapshot = new Snapshot(mFirstSnapshot,
+            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
+    mSaveCount = 1;
 }
 
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