hwc: Replace bytes claimed with bandwidth claimed.

Bytes claimed doesn't reflect the panel refresh rate.
So use the bandwidth claimed instead which factors this in.

This is important when 2 displays are running at different
refresh rates.

Change-Id: I3ab9573e43b8c25c31e01888fb2b181469b9e91b
diff --git a/libhwcomposer/hwc_mdpcomp.h b/libhwcomposer/hwc_mdpcomp.h
index 7063d32..5856946 100644
--- a/libhwcomposer/hwc_mdpcomp.h
+++ b/libhwcomposer/hwc_mdpcomp.h
@@ -52,7 +52,7 @@
     /* Initialize MDP comp*/
     static bool init(hwc_context_t *ctx);
     static void resetIdleFallBack() { sIdleFallBack = false; }
-    static void reset() { sCompBytesClaimed = 0; };
+    static void reset() { sBwClaimed = 0.0; };
 
 protected:
     enum { MAX_SEC_LAYERS = 1 }; //TODO add property support
@@ -205,9 +205,9 @@
     static int sMaxPipesPerMixer;
     //Max bandwidth. Value is in GBPS. For ex: 2.3 means 2.3GBPS
     static float sMaxBw;
-    //Tracks composition bytes claimed. Represented as the total w*h*bpp
-    //going to MDP mixers
-    static uint32_t sCompBytesClaimed;
+    //Tracks composition bandwidth claimed. Represented as the total
+    //w*h*bpp*fps (gigabytes-per-second) going to MDP mixers.
+    static double sBwClaimed;
     static IdleInvalidator *idleInvalidator;
     struct FrameInfo mCurrentFrame;
     struct LayerCache mCachedFrame;