Fix emulator's UI build

When building emulator-ui, build fails complaining that android_startOpenglesRenderer
implementation doesn't match routine declaration. Fixing that.

Change-Id: I5f3f588969c1b4c9a59035f8abddb63cc6c917ad
diff --git a/android/opengles.c b/android/opengles.c
index 6f0556f..b265428 100644
--- a/android/opengles.c
+++ b/android/opengles.c
@@ -278,7 +278,7 @@
     return -1;
 }
 
-int android_startOpenglesRenderer(int width, int height, OnPostFunc onPost, void* onPostContext)
+int android_startOpenglesRenderer(int width, int height)
 {
     return -1;
 }