[wasm] Fix generated function name when logging code.

R=herhut@chromium.org

Change-Id: Ic7fede18b89a14a8e0af255add5678a70b699475
Reviewed-on: https://chromium-review.googlesource.com/c/1319580Reviewed-by: Stephan Herhut <herhut@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57277}

src/wasm/wasm-code-manager.cc

@@ -169,7 +169,8 @@ void WasmCode::LogCode(Isolate* isolate) const {
                             {cname.get(), static_cast<size_t>(name_length)}));
   } else {
     EmbeddedVector<char, 32> generated_name;
-    SNPrintF(generated_name, "wasm-function[%d]", index());
+    int length = SNPrintF(generated_name, "wasm-function[%d]", index());
+    generated_name.Truncate(length);
     PROFILE(isolate, CodeCreateEvent(CodeEventListener::FUNCTION_TAG, this,
                                      generated_name));
   }