revert: refactor(mocks): simplify the inject implementation

This reverts commit 64d58a5b52.

For some weird reason this is causing regressions at Google.
I'm not sure why and I'm running out of time to investigate, so I'm taking
a safe route here and reverting the commit since it's just a refactoring.

src/ngMock/angular-mocks.js

@@ -2095,7 +2095,7 @@ if(window.jasmine || window.mocha) {
   window.inject = angular.mock.inject = function() {
     var blockFns = Array.prototype.slice.call(arguments, 0);
     var errorForStack = new Error('Declaration Location');
-    return isSpecRunning() ? workFn() : workFn;
+    return isSpecRunning() ? workFn.call(currentSpec) : workFn;
     /////////////////////
     function workFn() {
       var modules = currentSpec.$modules || [];
@@ -2108,8 +2108,9 @@ if(window.jasmine || window.mocha) {
       }
       for(var i = 0, ii = blockFns.length; i < ii; i++) {
         try {
-          // jasmine sets this to be the current spec, so we are mimicing that
-          injector.invoke(blockFns[i] || angular.noop, currentSpec);
+          /* jshint -W040 *//* Jasmine explicitly provides a `this` object when calling functions */
+          injector.invoke(blockFns[i] || angular.noop, this);
+          /* jshint +W040 */
         } catch (e) {
           if (e.stack && errorForStack) {
             throw new ErrorAddingDeclarationLocationStack(e, errorForStack);