Fix gles2 shader mixed_return_break_continue test to use proper loop form.

- Fix for counter form to not exceed limitations defined in Appendix A.

Bug: 19678840
Change-Id: Id2cf5987fa60c8c79c8c85c500624d332233223a
diff --git a/data/gles2/shaders/functions.test b/data/gles2/shaders/functions.test
index 62f8879..3f03112 100644
--- a/data/gles2/shaders/functions.test
+++ b/data/gles2/shaders/functions.test
@@ -2409,8 +2409,7 @@
 
 			float func (float a)
 			{
-				int i;
-				for (i = 0; i < 6; i++)
+				for (int i = 0; i < 6; i++)
 				{
 					if (i == 0)
 						continue;