Fix bug where CPU could be stuck spinning
Required the wallpaper be animating and
the system to have run slowly during the
last frame when rendering stopped.

bug 5180240

Change-Id: I38c2b6f07a1e36019dd05c77a58973e36d12728c
diff --git a/rsContext.cpp b/rsContext.cpp
index 2d51208..948ecf9 100644
--- a/rsContext.cpp
+++ b/rsContext.cpp
@@ -279,6 +279,8 @@
             rsc->timerSet(RS_TIMER_INTERNAL);
             rsc->timerPrint();
             rsc->timerReset();
+        } else {
+            doWait = true;
         }
     }