fix(web-server): Restart disconnected browser in non-singleRun mode.

Allow browserDisconnectTolerance config option to be set in non-singleRun mode.

In some cases, the browser would get stuck in an infinite loop (e.g. because of
a faulty code/test). This blocks browser’s event loop, preventing it from
reporting back to Karma. Karma then considers the browser ‘DISCONNECTED’.

Prior to this commit, the `browserDisconnectTolerance` option will only apply
in singleRun mode. In above scenario, the end-user must restart Karma to
continue running tests inside Karma-managed browsers. This commit fixes this
problem by always honoring the aforementioned option.

lib/config.js

@@ -145,11 +145,6 @@ var normalizeConfig = function (config, configFilePath) {
     config.autoWatch = false
   }
 
-  if (!config.singleRun && config.browserDisconnectTolerance) {
-    log.debug('browserDisconnectTolerance set to 0, because of singleRun')
-    config.browserDisconnectTolerance = 0
-  }
-
   if (helper.isString(config.reporters)) {
     config.reporters = config.reporters.split(',')
   }

lib/server.js

@@ -292,26 +292,34 @@ Server.prototype._start = function (config, launcher, preprocess, fileList, webS
     }
   }
 
-  if (config.singleRun) {
-    self.on('browser_complete', function (completedBrowser) {
-      if (completedBrowser.lastResult.disconnected &&
-        completedBrowser.disconnectsCount <= config.browserDisconnectTolerance) {
-        self.log.info('Restarting %s (%d of %d attempts)', completedBrowser.name,
-          completedBrowser.disconnectsCount, config.browserDisconnectTolerance)
-        if (!launcher.restart(completedBrowser.id)) {
-          singleRunDoneBrowsers[completedBrowser.id] = true
-          emitRunCompleteIfAllBrowsersDone()
-        }
-      } else {
-        singleRunDoneBrowsers[completedBrowser.id] = true
+  self.on('browser_complete', function (completedBrowser) {
+    if (completedBrowser.lastResult.disconnected &&
+      completedBrowser.disconnectsCount <= config.browserDisconnectTolerance) {
+      self.log.info('Restarting %s (%d of %d attempts)', completedBrowser.name,
+        completedBrowser.disconnectsCount, config.browserDisconnectTolerance)
+
+      if (!launcher.restart(completedBrowser.id)) {
+        self.emit('browser_restart_failure', completedBrowser)
+      }
+    } else {
+      self.emit('browser_complete_with_no_more_retries', completedBrowser)
+    }
+  })
 
-        if (launcher.kill(completedBrowser.id)) {
-          // workaround to supress "disconnect" warning
-          completedBrowser.state = Browser.STATE_DISCONNECTED
-        }
+  if (config.singleRun) {
+    self.on('browser_restart_failure', function (completedBrowser) {
+      singleRunDoneBrowsers[completedBrowser.id] = true
+      emitRunCompleteIfAllBrowsersDone()
+    })
+    self.on('browser_complete_with_no_more_retries', function (completedBrowser) {
+      singleRunDoneBrowsers[completedBrowser.id] = true
 
-        emitRunCompleteIfAllBrowsersDone()
+      if (launcher.kill(completedBrowser.id)) {
+        // workaround to supress "disconnect" warning
+        completedBrowser.state = Browser.STATE_DISCONNECTED
       }
+
+      emitRunCompleteIfAllBrowsersDone()
     })
 
     self.on('browser_process_failure', function (browserLauncher) {