Bug 1437696 Reset console after BrowserErrorReporter tests. r=gijs

Because BrowserErrorReporter instances process previously-logged messages when
they are initialized, multiple runs of each test case (such as during the test
verification suite) cause new instances to process messages from the previous
test run. Resetting the console at the end of each test case prevents tests from
affecting each other.

Differential Revision: https://phabricator.services.mozilla.com/D589

MozReview-Commit-ID: HwjbbE00o97

--HG--
extra : rebase_source : 94ea69f8dbe679ff228c5c9b016f131650be1671
extra : amend_source : 5a9d0b5018d28d2dfc4782e66c732b711cb67109

browser/modules/test/browser/browser_BrowserErrorReporter.js

@@ -46,6 +46,13 @@ function logMessage(message) {
   });
 }
 
+// Clears the console of any previous messages. Should be called at the end of
+// each test that logs to the console.
+function resetConsole() {
+  Services.console.logStringMessage("");
+  Services.console.reset();
+}
+
 // Wrapper similar to logMessage, but for logStringMessage.
 function logStringMessage(message) {
   return new Promise(resolve => {
@@ -94,6 +101,7 @@ add_task(async function testInitPrefDisabled() {
     "Reporter does not listen for errors if the enabled pref is false.",
   );
   reporter.uninit();
+  resetConsole();
 });
 
 add_task(async function testInitUninitPrefEnabled() {
@@ -119,6 +127,8 @@ add_task(async function testInitUninitPrefEnabled() {
     !fetchPassedError(fetch, "Logged after uninit"),
     "Reporter does not listen for errors after uninit.",
   );
+
+  resetConsole();
 });
 
 add_task(async function testInitPastMessages() {
@@ -136,6 +146,7 @@ add_task(async function testInitPastMessages() {
     "Reporter collects errors logged before initialization.",
   );
   reporter.uninit();
+  resetConsole();
 });
 
 add_task(async function testEnabledPrefWatcher() {
@@ -167,6 +178,7 @@ add_task(async function testEnabledPrefWatcher() {
   );
 
   reporter.uninit();
+  resetConsole();
 });
 
 add_task(async function testNonErrorLogs() {
@@ -210,6 +222,7 @@ add_task(async function testNonErrorLogs() {
   );
 
   reporter.uninit();
+  resetConsole();
 });
 
 add_task(async function testSampling() {
@@ -244,6 +257,9 @@ add_task(async function testSampling() {
     !fetchPassedError(fetch, "Also shouldn't log"),
     "An invalid sample rate will cause the reporter to never collect errors.",
   );
+
+  reporter.uninit();
+  resetConsole();
 });
 
 add_task(async function testNameMessage() {
@@ -297,6 +313,7 @@ add_task(async function testNameMessage() {
     "Reporter uses error message as the value parameter.",
   );
   reporter.uninit();
+  resetConsole();
 });
 
 add_task(async function testFetchArguments() {
@@ -384,4 +401,7 @@ add_task(async function testFetchArguments() {
       "Reporter builds stack trace from scriptError correctly.",
     );
   });
+
+  reporter.uninit();
+  resetConsole();
 });