[wasm] Include source URL in tracing

For streaming compilation, include the source URL in tracing, to
help identifying problems with caching.

R=ahaas@chromium.org

Change-Id: Iefda71890024a4fc9ec933c34c5870ba697bbff9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3289148Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77950}

src/wasm/wasm-js.cc

@@ -137,7 +137,8 @@ void WasmStreaming::SetClient(std::shared_ptr<Client> client) {
 }
 
 void WasmStreaming::SetUrl(const char* url, size_t length) {
-  TRACE_EVENT0("v8.wasm", "wasm.SetUrl");
+  DCHECK_EQ('\0', url[length]);  // {url} is null-terminated.
+  TRACE_EVENT1("v8.wasm", "wasm.SetUrl", "url", url);
   impl_->SetUrl(base::VectorOf(url, length));
 }