fix(ngMock): trigger digest in $httpBackend.verifyNoOutstandingRequest()

Firing a digest at the beginning of the verification process, ensures that requests fired
asynchronously - e.g. in the `resolve` handler of a promise as happens with `$http` - will get
detected as well.
Previously, in order to reliably verify that there was no outstanding request, users needed to
manually trigger a digest, before calling `verifyNoOutstandingRequest()`. Failing to do so, could
prevent `verifyNoOutstandingRequest()` from detecting pending requests and cover bugs in application
code.
This is no longer the case, since a digest will always be fired autommatically as part of a call to
`verifyNoOutstandingRequest()`.

Fixes angular#13506
Closes angular#13513

BREAKING CHANGE:

Calling `$httpBackend.verifyNoOutstandingRequest()` will trigger a digest. This will ensure that
requests fired asynchronously will also be detected (without the need to manually trigger a digest).
This is not expected to affect the majority of test-suites. Most of the time, a digest is (directly
or indirectly) triggered anyway, before calling `verifyNoOutstandingRequest()`.
In the unlikely case that a test needs to verify the timing of a request with respect to the digest
cycle, you should rely on other means, such as mocking and/or spying.

Author: katemihalikova

src/ngMock/angular-mocks.js

@@ -1847,7 +1847,8 @@ function createHttpBackendMock($rootScope, $timeout, $delegate, $browser) {
    *   afterEach($httpBackend.verifyNoOutstandingRequest);
    * ```
    */
-  $httpBackend.verifyNoOutstandingRequest = function() {
+  $httpBackend.verifyNoOutstandingRequest = function(digest) {
+    if (digest !== false) $rootScope.$digest();
     if (responses.length) {
       throw new Error('Unflushed requests: ' + responses.length);
     }

test/ngMock/angular-mocksSpec.js

@@ -1012,6 +1012,7 @@ describe('ngMock', function() {
       hb = $httpBackend;
     }));
 
+
     it('should provide "expect" methods for each HTTP verb', function() {
       expect(typeof hb.expectGET).toBe("function");
       expect(typeof hb.expectPOST).toBe("function");
@@ -1031,6 +1032,7 @@ describe('ngMock', function() {
       expect(typeof hb.whenHEAD).toBe("function");
     });
 
+
     it('should provide "route" shortcuts for expect and when', function() {
       expect(typeof hb.whenRoute).toBe("function");
       expect(typeof hb.expectRoute).toBe("function");
@@ -1653,6 +1655,7 @@ describe('ngMock', function() {
       });
     });
 
+
     describe('verifyRequests', function() {
 
       it('should throw exception if not all requests were flushed', function() {
@@ -1663,6 +1666,18 @@ describe('ngMock', function() {
           hb.verifyNoOutstandingRequest();
         }).toThrowError('Unflushed requests: 1');
       });
+
+
+      it('should verify requests fired asynchronously', inject(function($q) {
+        hb.when('GET').respond(200);
+        $q.resolve().then(function() {
+          hb('GET', '/some', null, noop, {});
+        });
+
+        expect(function() {
+          hb.verifyNoOutstandingRequest();
+        }).toThrowError('Unflushed requests: 1');
+      }));
     });
 
 
@@ -1723,6 +1738,7 @@ describe('ngMock', function() {
       });
     });
 
+
     describe('expectRoute/whenRoute shortcuts', function() {
       angular.forEach(['expectRoute', 'whenRoute'], function(routeShortcut) {
         var methods = ['GET', 'POST', 'PUT', 'PATCH', 'DELETE', 'JSONP'];
@@ -1753,6 +1769,7 @@ describe('ngMock', function() {
       });
     });
 
+
     describe('MockHttpExpectation', function() {
       /* global MockHttpExpectation */