Coerce non error objects into errors before sending to sentry (#1874)

* Coerce non error objects into errors

It seems like we're passing non errors to sentry

re: https://sentry.io/organizations/metamask/issues/1641747298/?project=2299799&query=is%3Aunresolved&statsPeriod=14d

I realise we should fix this underlying issue, but adding this will allow us to make mistakes without upsetting the Sentry gods
At least, that's my hope 🙏

app/util/Logger.js

@@ -43,16 +43,31 @@ export default class Logger {
 		if (__DEV__) {
 			console.warn(DEBUG, error); // eslint-disable-line no-console
 		} else if (metricsOptIn === AGREED) {
+			let exception = error.error || error.message || error.originalError || error;
+			if (!(error instanceof Error)) {
+				const type = typeof error;
+				switch (type) {
+					case 'string':
+						exception = new Error(error);
+						break;
+					case 'object':
+						exception = new Error(JSON.stringify(error));
+						break;
+					default:
+						exception = new Error('error to capture is not an error instance');
+				}
+				exception.originalError = error;
+			}
 			if (extra) {
 				if (typeof extra === 'string') {
 					extra = { message: extra };
 				}
 				withScope(scope => {
 					scope.setExtras(extra);
-					captureException(error);
+					captureException(exception);
 				});
 			} else {
-				captureException(error);
+				captureException(exception);
 			}
 		}
 	}