Wait for toggle_touch_event_logging to exit so we don't leave zombie processes

BUG=376806
TEST=bring up/dismiss the virtual keyboard a few times and then run ps aux to
make sure there is no defunct chrome process.

Review URL: https://codereview.chromium.org/297173003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@273064 0039d316-1c4b-4281-b951-d872f2087c98

ui/keyboard/keyboard_controller.cc

@@ -129,7 +129,9 @@ void ToggleTouchEventLogging(bool enable) {
   else
     command.AppendArg("0");
   VLOG(1) << "Running " << command.GetCommandLineString();
-  base::LaunchProcess(command, base::LaunchOptions(), NULL);
+  base::LaunchOptions options;
+  options.wait = true;
+  base::LaunchProcess(command, options, NULL);
 #endif
 }