base: Remove the string logging from CHECK().

chrome/test/media_router/media_router_integration_browsertest.cc

Index: chrome/test/media_router/media_router_integration_browsertest.cc
diff --git a/chrome/test/media_router/media_router_integration_browsertest.cc b/chrome/test/media_router/media_router_integration_browsertest.cc
index 32a5e7de342edaa59860ce9dde37854c184687d2..1d2b79d2ffde89842e934feaf8b0c0ec8281b8be 100644
--- a/chrome/test/media_router/media_router_integration_browsertest.cc
+++ b/chrome/test/media_router/media_router_integration_browsertest.cc
@@ -249,7 +249,8 @@ void MediaRouterIntegrationBrowserTest::SetTestData(
   std::string error_message;
   std::unique_ptr<base::Value> value =
       deserializer.Deserialize(&error_code, &error_message);
-  CHECK(value.get()) << "Deserialize failed: " << error_message;
+  // Deserialize failed.
+  CHECK(value.get());
   std::string test_data_str;
   ASSERT_TRUE(base::JSONWriter::Write(*value, &test_data_str));
   ExecuteScriptInBackgroundPageNoWait(