Disable GLOOBAttribTest on passthrough.

The passthrough command decoder uses robust buffer access behaviour. This
makes OOB error checks unimportant because OOB accesses will not cause
errors. OOB accesses will also return implementation-dependent values.
See the KHR_robust_buffer_access_behavior spec for more information.

This will allow ANGLE to selectively disable range checking when robust
buffer access behaviour is enabled. This applies to DrawArrays calls
only. DrawElements already had the robust buffer access check instated.

Bug: angleproject:3000
Change-Id: I3bf5f694d740025a9c40142bb5b0a7801489a70a
Reviewed-on: https://chromium-review.googlesource.com/c/1396298Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619996}

gpu/command_buffer/tests/gl_oob_attrib_unittest.cc

@@ -24,6 +24,15 @@ class GLOOBAttribTest : public testing::Test {
 // Tests that enabling a vertex array for a location that matches any column of
 // a matrix attribute correctly triggers out-of-bounds checks.
 TEST_F(GLOOBAttribTest, DrawUsingOOBMatrixAttrib) {
+  // The passthrough command decoder uses robust buffer access behaviour. This
+  // makes OOB error checks unimportant because OOB accesses will not cause
+  // errors. OOB accesses will also return implementation-dependent values.
+  // See the KHR_robust_buffer_access_behavior spec for more information.
+  if (gl_.gpu_preferences().use_passthrough_cmd_decoder) {
+    std::cout << "Test skipped, KHR_robust_buffer_access_behavior enabled.\n";
+    return;
+  }
+
   const char kVertexShader[] =
       "attribute mat3 attrib;\n"
       "varying vec4 color;\n"