Compute dirty regions aggressivelylinaro_android_2.3.3

The exposed region consists of two components:
    1) What's VISIBLE now and was COVERED before
    2) What's EXPOSED now less that was EXPOSED before

However, the first component should be regarded as dirty
region in above layer.  For efficiency reason we compute
dirty region aggressively.

Signed-off-by: Jim Huang <jim.huang@linaro.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 4876946f2b3d..23c8409f3b2c 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -681,7 +681,7 @@ void SurfaceFlinger::computeVisibleRegions(
             const Region oldVisibleRegion = layer->visibleRegionScreen;
             const Region oldCoveredRegion = layer->coveredRegionScreen;
             const Region oldExposed = oldVisibleRegion - oldCoveredRegion;
-            dirty = (visibleRegion&oldCoveredRegion) | (newExposed-oldExposed);
+            dirty = (newExposed-oldExposed);
         }
         dirty.subtractSelf(aboveOpaqueLayers);