gpu/khronos_glcts_support: skip Texture_Rectangle_Samplers_frag test

Chromium implements GL_ARB_texture_rectangle which makes this
test fail.

Add this test to the test expectations so it will be skipped.

BUG=chromium:139729, chromium:412865
R=kbr@chromium.org, piman@chromium.org
TEST=Build and run khronos_glcts_test binary. Ensure test is skipped.

Signed-off-by: U. Artie Eoff <ullysses.a.eoff@intel.com>

Review URL: https://codereview.chromium.org/641913002

Cr-Commit-Position: refs/heads/master@{#298939}

gpu/khronos_glcts_support/khronos_glcts_test_expectations.txt

@@ -24,6 +24,8 @@
 //  91531 MAC WIN LINUX : conformance_more_* = SKIP
 //  91532 MAC NVIDIA 0x0640 : tex_image_and_sub_image_2d_with_video = PASS FAIL
 
+// Chromium implements GL_ARB_texture_rectangle which makes this test fail
+139729 DEBUG RELEASE : ES2_CTS_gtf_GL_build_Texture_Rectangle_Samplers_frag = FAIL
 
 ////////////////////////////////////////////////////////////////////////////////
 //