[Piglit] [PATCH] Fix clearbuffer-display-lists test case

[Anuj Phogat]

glClear(GL_COLOR_BUFFER_BIT) before probing the color buffer.
Test occasionally fails without this call.

Reported-by: Eric Anholt <eric at anholt.net>
Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
---
 tests/spec/gl-3.0/api/clearbuffer-display-lists.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/spec/gl-3.0/api/clearbuffer-display-lists.c b/tests/spec/gl-3.0/api/clearbuffer-display-lists.c
index 8595076..7924f91 100644
--- a/tests/spec/gl-3.0/api/clearbuffer-display-lists.c
+++ b/tests/spec/gl-3.0/api/clearbuffer-display-lists.c
@@ -44,8 +44,10 @@ void piglit_init(int argc, char **argv)
 	bool pass = true;
 
 	piglit_require_gl_version(30);
-	/* Probe the color buffer before creating display list. color buffers
-	 * are by default cleared to (0.0, 0.0, 0.0, 1.0)
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	/* Probe the color buffer before creating display list. Default clear
+	 * color is (0.0, 0.0, 0.0, 1.0)
 	 */
 	pass = piglit_probe_rect_rgba(0, 0,
 				      piglit_width, piglit_height,
-- 
1.7.7.4