Disable cfguard for tcu/depq test files

These seem to be generated with bad unwinding and cause crashes when
exceptions are unwound.

Specifically

tcu::TestStatus RandomOrderExecutor::executeInner(TestCase *testCase,
                         const std::string &casePath)

can be built with __declspec(guard(nocf).

Test: CQ
    .\out\swangle\angle_deqp_gles2_tests.exe --use-angle=swiftshader --gtest_filter=dEQP.GLES2/functional_multisample_common_edge_big_quad --bot-mode
Bug: angleproject:6617
Change-Id: Iae75dc0f911a3430276909f4a14944d0f805fdf2
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3241703
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>

src/tests/BUILD.gn

@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import("//build/config/chromecast_build.gni")
+import("//build/config/win/control_flow_guard.gni")
 import("//testing/test.gni")
 import("../../gni/angle.gni")
 import("angle_unittests.gni")
@@ -1257,6 +1258,11 @@ if (build_angle_deqp_tests && !is_fuchsia) {
       ":angle_deqp_libtester_config",
       "${angle_root}:libANGLE_config",
     ]
+    if (is_win && target_cpu == "x86" && win_enable_cfg_guards) {
+      # See crbug.com/1260874 tcuRandomOrderExecutor produces bad
+      # unwinding if compiled with cfg guards for x86.
+      configs += [ "//build/config/win:disable_guards_cfg_compiler" ]
+    }
     sources = deqp_libtester_sources
     if (is_android) {
       libs = [ "log" ]