add bench for building blurs



git-svn-id: http://skia.googlecode.com/svn/trunk@1865 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/bench/benchmain.cpp b/bench/benchmain.cpp
index 29963a8..89909ca 100644
--- a/bench/benchmain.cpp
+++ b/bench/benchmain.cpp
@@ -479,6 +479,12 @@
             for (int i = 0; i < repeatDraw; i++) {
                 SkAutoCanvasRestore acr(&canvas, true);
                 bench->draw(&canvas);
+                if (gpu) {
+                    context->flush();
+                }
+            }
+            if (gpu) {
+                glFinish();
             }
             timer.end();