Disable WebUI's JavaScript Error reporting for MediaApp

Media App already has its own error reporting system; don't send
duplicate reports via WebUI.

Bug: chromium:1121816
Change-Id: Ia0c4410cf7cda9a87a92bffd269421f9d0575bbd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2556446Reviewed-by: dstockwell <dstockwell@google.com>
Commit-Queue: dstockwell <dstockwell@google.com>
Auto-Submit: Ian Barkley-Yeung <iby@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830815}

chromeos/components/media_app_ui/media_app_ui.cc

@@ -96,6 +96,10 @@ MediaAppUI::MediaAppUI(content::WebUI* web_ui,
 
   // Add ability to request chrome-untrusted: URLs.
   web_ui->AddRequestableScheme(content::kChromeUIUntrustedScheme);
+
+  // JavaScript errors are reported via CrashReportPrivate.reportError. Don't
+  // send duplicate reports via WebUI.
+  web_ui->DisableJavaScriptErrorReporting();
 }
 
 MediaAppUI::~MediaAppUI() = default;