Revert "Delete HWC1"

This reverts commit 90f923493fa053655a203c34ea491086aeb07602.

Change-Id: If9da49e3bc85f8ff21ac1bd22a6bab97e9aa3103
diff --git a/services/surfaceflinger/EventControlThread.cpp b/services/surfaceflinger/EventControlThread.cpp
index 26822c8..ee6e886 100644
--- a/services/surfaceflinger/EventControlThread.cpp
+++ b/services/surfaceflinger/EventControlThread.cpp
@@ -35,7 +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);
@@ -46,7 +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;
         }
     }