hwc: Calculate viewframe from layers display frame information.

Calculate view frame of each display from the displayframe of all
the application layers.

Change-Id: I9ba4076b7b4419bd3559417fad28b4e1de6acff3
diff --git a/libhwcomposer/hwc_utils.h b/libhwcomposer/hwc_utils.h
index 2503e43..95ecf2c 100644
--- a/libhwcomposer/hwc_utils.h
+++ b/libhwcomposer/hwc_utils.h
@@ -437,6 +437,7 @@
     qhwc::LayerProp *layerProp[HWC_NUM_DISPLAY_TYPES];
     qhwc::MDPComp *mMDPComp[HWC_NUM_DISPLAY_TYPES];
     qhwc::HwcDebug *mHwcDebug[HWC_NUM_DISPLAY_TYPES];
+    hwc_rect_t mViewFrame[HWC_NUM_DISPLAY_TYPES];
     qhwc::AssertiveDisplay *mAD;
     qhwc::VPUClient *mVPUClient;