base: Remove the string logging from CHECK().

content/browser/browser_plugin/browser_plugin_guest.cc

Index: content/browser/browser_plugin/browser_plugin_guest.cc
diff --git a/content/browser/browser_plugin/browser_plugin_guest.cc b/content/browser/browser_plugin/browser_plugin_guest.cc
index d4d4f14d881c1e6f02b7efe8578dc5bbd3785819..ee97ff002aef88c0180444bbb51b0b1f704f0700 100644
--- a/content/browser/browser_plugin/browser_plugin_guest.cc
+++ b/content/browser/browser_plugin/browser_plugin_guest.cc
@@ -609,11 +609,11 @@ std::unique_ptr<IPC::Message> BrowserPluginGuest::UpdateInstanceIdIfNecessary(
   size_t remaining_bytes = msg->payload_size() - sizeof(int);
   const char* data = nullptr;
   bool read_success = iter.ReadBytes(&data, remaining_bytes);
-  CHECK(read_success)
-      << "Unexpected failure reading remaining IPC::Message payload.";
+  // Unexpected failure reading remaining IPC::Message payload.
+  CHECK(read_success);
   bool write_success = new_msg->WriteBytes(data, remaining_bytes);
-  CHECK(write_success)
-      << "Unexpected failure writing remaining IPC::Message payload.";
+  // Unexpected failure writing remaining IPC::Message payload.
+  CHECK(write_success);
 
   return new_msg;
 }