Switch SurfaceFlinger to HWC 2.0

Enables SurfaceFlinger to speak to version 2.0 of the Hardware Composer
HAL instead of version 1.x (also removing support for the framebuffer
HAL). By default, however, this functionality is disabled. In order to
enable it, USE_HWC2 must be set to true in Android.mk.

Change-Id: I4589e02ac2165236b10ff2f7cb772f87e0d3daab
diff --git a/services/surfaceflinger/EventControlThread.cpp b/services/surfaceflinger/EventControlThread.cpp
index 6504091..ee6e886 100644
--- a/services/surfaceflinger/EventControlThread.cpp
+++ b/services/surfaceflinger/EventControlThread.cpp
@@ -35,8 +35,12 @@
 
     bool vsyncEnabled = mVsyncEnabled;
 
+#ifdef USE_HWC2
+    mFlinger->setVsyncEnabled(HWC_DISPLAY_PRIMARY, mVsyncEnabled);
+#else
     mFlinger->eventControl(HWC_DISPLAY_PRIMARY, SurfaceFlinger::EVENT_VSYNC,
             mVsyncEnabled);
+#endif
 
     while (true) {
         status_t err = mCond.wait(mMutex);
@@ -47,8 +51,12 @@
         }
 
         if (vsyncEnabled != mVsyncEnabled) {
+#ifdef USE_HWC2
+            mFlinger->setVsyncEnabled(HWC_DISPLAY_PRIMARY, mVsyncEnabled);
+#else
             mFlinger->eventControl(HWC_DISPLAY_PRIMARY,
                     SurfaceFlinger::EVENT_VSYNC, mVsyncEnabled);
+#endif
             vsyncEnabled = mVsyncEnabled;
         }
     }