hwc: Crop source rect for the optimized destination

If a layer destination can be optimized, its source rect
needs to be cropped for the optimized destination rect.

Change-Id: If9a9891200d9cea52b58b253299b4007197cd9e5

libhwcomposer/hwc_utils.cpp

@@ -1056,10 +1056,11 @@ void optimizeLayerRects(hwc_context_t *ctx,
 
                   hwc_rect_t irect = getIntersection(bottomframe, topframe);
                   if(isValidRect(irect)) {
+                     hwc_rect_t dest_rect;
                      //if intersection is valid rect, deduct it
-                     bottomframe = deductRect(bottomframe, irect);
+                     dest_rect  = deductRect(bottomframe, irect);
                      qhwc::calculate_crop_rects(bottomCrop, bottomframe,
-                                                bottomframe, transform);
+                                                dest_rect, transform);
 
                   }
                }