Cleanup FIRApp Auth Code

This is no longer necessary due to the interop process now being in place.

+ Deleted `getTokenForcingRefresh:withCallback:` from FIRApp
+ Deleted `getUID` from FIRApp
+ Deleted related code from FIRAuth
+ Deleted tests related to deleted code

Author: bstpierr

Example/Auth/Tests/FIRAuthTests.m

@@ -365,20 +365,6 @@ - (void)testLifeCycle {
   XCTAssertNil(auth);
 }
 
-/** @fn testGetUID
-    @brief Verifies that FIRApp's getUIDImplementation is correctly set by FIRAuth.
- */
-- (void)testGetUID {
-  // TODO: Remove this test once Firestore, Database, and Storage move over to the new Auth interop
-  //       library.
-  FIRApp *app = [FIRApp defaultApp];
-  XCTAssertNotNil(app.getUIDImplementation);
-  [[FIRAuth auth] signOut:NULL];
-  XCTAssertNil(app.getUIDImplementation());
-  [self waitForSignIn];
-  XCTAssertEqualObjects(app.getUIDImplementation(), kLocalID);
-}
-
 #pragma mark - Server API Tests
 
 /** @fn testFetchProvidersForEmailSuccess
@@ -2277,19 +2263,6 @@ - (void)mockSecureTokenResponseWithError:(nullable NSError *)error {
   });
 }
 
-/** @fn enableAutoTokenRefresh
-    @brief Enables automatic token refresh by invoking FIRAuth's implementation of FIRApp's
-        |getTokenWithImplementation|.
- */
-- (void)enableAutoTokenRefresh {
-  XCTestExpectation *expectation = [self expectationWithDescription:@"autoTokenRefreshcallback"];
-  [[FIRAuth auth].app getTokenForcingRefresh:NO withCallback:^(NSString *_Nullable token,
-                                                                NSError *_Nullable error) {
-    [expectation fulfill];
-  }];
-  [self waitForExpectationsWithTimeout:kExpectationTimeout handler:nil];
-}
-
 /** @fn app1
     @brief Creates a Firebase app.
     @return A @c FIRApp with some name.

Example/Core/Tests/FIRAppTest.m

@@ -283,59 +283,6 @@ - (void)testErrorForSubspecConfigurationFailure {
   XCTAssert([error.description containsString:@"Configuration failed for"]);
 }
 
-- (void)testGetTokenWithCallback {
-  [FIRApp configure];
-  FIRApp *app = [FIRApp defaultApp];
-
-  __block BOOL getTokenImplementationWasCalled = NO;
-  __block BOOL getTokenCallbackWasCalled = NO;
-  __block BOOL passedRefreshValue = NO;
-
-  [app getTokenForcingRefresh:YES
-                 withCallback:^(NSString *_Nullable token, NSError *_Nullable error) {
-                   getTokenCallbackWasCalled = YES;
-                 }];
-
-  XCTAssert(getTokenCallbackWasCalled,
-            @"The callback should be invoked by the base implementation when no block for "
-             "'getTokenImplementation' has been specified.");
-
-  getTokenCallbackWasCalled = NO;
-
-  app.getTokenImplementation = ^(BOOL refresh, FIRTokenCallback callback) {
-    getTokenImplementationWasCalled = YES;
-    passedRefreshValue = refresh;
-    callback(nil, nil);
-  };
-  [app getTokenForcingRefresh:YES
-                 withCallback:^(NSString *_Nullable token, NSError *_Nullable error) {
-                   getTokenCallbackWasCalled = YES;
-                 }];
-
-  XCTAssert(getTokenImplementationWasCalled,
-            @"The 'getTokenImplementation' block was never called.");
-  XCTAssert(passedRefreshValue,
-            @"The value for the 'refresh' parameter wasn't passed to the 'getTokenImplementation' "
-             "block correctly.");
-  XCTAssert(getTokenCallbackWasCalled,
-            @"The 'getTokenImplementation' should have invoked the callback. This could be an "
-             "error in this test, or the callback parameter may not have been passed to the "
-             "implementation correctly.");
-
-  getTokenImplementationWasCalled = NO;
-  getTokenCallbackWasCalled = NO;
-  passedRefreshValue = NO;
-
-  [app getTokenForcingRefresh:NO
-                 withCallback:^(NSString *_Nullable token, NSError *_Nullable error) {
-                   getTokenCallbackWasCalled = YES;
-                 }];
-
-  XCTAssertFalse(passedRefreshValue,
-                 @"The value for the 'refresh' parameter wasn't passed to the "
-                  "'getTokenImplementation' block correctly.");
-}
-
 - (void)testModifyingOptionsThrows {
   [FIRApp configure];
   FIROptions *options = [[FIRApp defaultApp] options];
@@ -754,16 +701,6 @@ - (void)testAnalyticsNotSetByGlobalDataCollectionSwitch {
 
 #pragma mark - Internal Methods
 
-// TODO: Remove this test once the `getUIDImplementation` block doesn't need to be set in Core.
-- (void)testAuthGetUID {
-  [FIRApp configure];
-
-  [FIRApp defaultApp].getUIDImplementation = ^NSString * {
-    return @"highlander";
-  };
-  XCTAssertEqual([[FIRApp defaultApp] getUID], @"highlander");
-}
-
 - (void)testIsAppConfigured {
   // Ensure it's false before anything is configured.
   XCTAssertFalse([FIRApp isDefaultAppConfigured]);