Suppress flaky OpenGL ES3 test.

Texture2DIntegerTestES3.IntegerTextureNonZeroBaseLevel/ES3_OpenGL

Bug: chromium:963595
Change-Id: I6cdd845a5b7bc1a4b5a16029eaf170db40f1787c
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1613894
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/tests/gl_tests/TextureTest.cpp b/src/tests/gl_tests/TextureTest.cpp
index 9de0ea0..ba105eb 100644
--- a/src/tests/gl_tests/TextureTest.cpp
+++ b/src/tests/gl_tests/TextureTest.cpp
@@ -4466,6 +4466,9 @@
 // texture is output.
 TEST_P(Texture2DIntegerTestES3, IntegerTextureNonZeroBaseLevel)
 {
+    // Flaky on Windows OpenGL drivers. http://crbug.com/963595
+    ANGLE_SKIP_TEST_IF(IsOpenGL() && IsWindows());
+
     glActiveTexture(GL_TEXTURE0);
     glBindTexture(GL_TEXTURE_2D, mTexture2D);
     int width     = getWindowWidth();