fix($templateRequest): always return the template that is stored in the cache

Previously, `$templateRequest` returned the raw `$http` response data on the
first request for a template and then the value from the cache for subsequent
requests.

If the value is transformed when being added to the cache (by decorating
`$templateCache.put`)  the return value of `$templateRequest` would be
inconsistent depending upon when the request is made.

This commit ensures the cached value is returned instead of the raw `$http`
response data, thus allowing the `$templateCache` service to be decorated.

Closes #16225

Author: frederikprijck

src/ng/templateRequest.js

@@ -99,8 +99,7 @@ function $TemplateRequestProvider() {
             handleRequestFn.totalPendingRequests--;
           })
           .then(function(response) {
-            $templateCache.put(tpl, response.data);
-            return response.data;
+            return $templateCache.put(tpl, response.data);
           }, handleError);
 
         function handleError(resp) {

test/ng/templateRequestSpec.js

@@ -114,6 +114,24 @@ describe('$templateRequest', function() {
     expect($templateCache.get('tpl.html')).toBe('matias');
   }));
 
+  it('should return the cached value on the first request',
+    inject(function($rootScope, $templateRequest, $templateCache, $httpBackend) {
+
+      $httpBackend.expectGET('tpl.html').respond('matias');
+      spyOn($templateCache, 'put').and.returnValue('_matias');
+
+      var content = [];
+      function tplRequestCb(html) {
+        content.push(html);
+      }
+
+      $templateRequest('tpl.html').then(tplRequestCb);
+      $rootScope.$digest();
+      $httpBackend.flush();
+
+      expect(content[0]).toBe('_matias');
+    }));
+
   it('should call `$exceptionHandler` on request error', function() {
     module(function($exceptionHandlerProvider) {
       $exceptionHandlerProvider.mode('log');