Gpu tests: Allow zero device ID on in Mac GPUTestBotConfig::SetGPUInfo

The ARM DTK does not specify a PCI device ID for the GPU. Do not fail
in this configuration. There are other places, GPUTestConfig::IsValid,
for instance, where we explicit allow a zero device ID.

Of note is that zero device IDs are allowed only when there is a
single GPU. ANGLE's current enumeration code will only enumerate
non-PCI devices once no PCI devices are found, so this is will
continue to work for the moment.

Bug: 1110421, 1121663, 1121672
Change-Id: I7cba1c4d074c291663913b970db3e4085afa0adc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2387308Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Reviewed-by: ccameron <ccameron@chromium.org>
Commit-Queue: ccameron <ccameron@chromium.org>
Cr-Commit-Position: refs/heads/master@{#803553}

gpu/config/gpu_test_config.cc

@@ -191,8 +191,14 @@ void GPUTestBotConfig::AddGPUVendor(uint32_t gpu_vendor) {
 }
 
 bool GPUTestBotConfig::SetGPUInfo(const GPUInfo& gpu_info) {
-  if (gpu_info.gpu.device_id == 0 || gpu_info.gpu.vendor_id == 0)
+  if (gpu_info.gpu.vendor_id == 0)
     return false;
+#if !defined(OS_MAC)
+  // ARM-based Mac GPUs do not have valid PCI device IDs.
+  // https://crbug.com/1110421
+  if (gpu_info.gpu.device_id == 0)
+    return false;
+#endif
   ClearGPUVendor();
   AddGPUVendor(gpu_info.gpu.vendor_id);
   set_gpu_device_id(gpu_info.gpu.device_id);