Fix fuzzer hang when waiting for fence signal after device loss

When the fuzzer passes the command DeviceLoseForTesting, the
DawnWireServerFuzzer will hang forever when waiting for a fence signal
because the device was lost. This commit sets a callback on device loss
which gives an extra condition to break the hang.

Bug: dawn:444

Change-Id: I0157358ed6da39cc6fcab7e1be8a3d5fde74266f
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/23141
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Natasha Lee <natlee@microsoft.com>
Commit-Queue: Brandon Jones <brandon1.jones@intel.com>

src/fuzzers/DawnWireServerFuzzer.cpp

@@ -50,6 +50,8 @@ namespace {
     std::string sInjectedErrorTestcaseOutDir;
     uint64_t sOutputFileNumber = 0;
 
+    bool sCommandsComplete = false;
+
     WGPUSwapChain ErrorDeviceCreateSwapChain(WGPUDevice device,
                                              WGPUSurface surface,
                                              const WGPUSwapChainDescriptor*) {
@@ -59,6 +61,10 @@ namespace {
         return sOriginalDeviceCreateSwapChain(device, surface, &desc);
     }
 
+    void CommandsCompleteCallback(WGPUFenceCompletionStatus status, void* userdata) {
+        sCommandsComplete = true;
+    }
+
 }  // namespace
 
 int DawnWireServerFuzzer::Initialize(int* argc, char*** argv) {
@@ -156,7 +162,8 @@ int DawnWireServerFuzzer::Run(const uint8_t* data,
         wgpu::Queue queue = device.GetDefaultQueue();
         wgpu::Fence fence = queue.CreateFence();
         queue.Signal(fence, 1u);
-        while (fence.GetCompletedValue() != 1u) {
+        fence.OnCompletion(1u, CommandsCompleteCallback, 0);
+        while (!sCommandsComplete) {
             device.Tick();
             utils::USleep(100);
         }