hwc: Dynamic Resolution support on Primary

    * Useful to estimate GPU/MDP performance for different resolutions.
    * MDP:
      Every layer is downscaled/upscaled to primary panel resolution.
    * GPU:
      All layers will be composed in required resolution to FB.
      FB is downscaled/upscaled to primary panel resolution.
    * Steps to follow:
          step 1: adb root
          step 2: adb shell setprop debug.hwc.fbsize XRESxYRES
          step 3: adb shell stop
          step 4: adb shell start

Change-Id: I82a032df87c91549c49a9cdbd981ff02f105ff2e
diff --git a/libhwcomposer/hwc_utils.h b/libhwcomposer/hwc_utils.h
index e64f89c..22debaf 100644
--- a/libhwcomposer/hwc_utils.h
+++ b/libhwcomposer/hwc_utils.h
@@ -35,6 +35,8 @@
 #define LIKELY( exp )       (__builtin_expect( (exp) != 0, true  ))
 #define UNLIKELY( exp )     (__builtin_expect( (exp) != 0, false ))
 #define MAX_NUM_APP_LAYERS 32
+#define MIN_DISPLAY_XRES 200
+#define MIN_DISPLAY_YRES 200
 
 //Fwrd decls
 struct hwc_context_t;
@@ -95,6 +97,13 @@
     bool mActionSafePresent;
     int mAsWidthRatio;
     int mAsHeightRatio;
+
+    //If property fbsize set via adb shell debug.hwc.fbsize = XRESxYRES
+    //following fields are used.
+    bool customFBSize;
+    uint32_t xres_orig;
+    uint32_t yres_orig;
+
 };
 
 struct ListStats {