Revert "Minimal test harness for iOS (#13029)" (#18631)

This reverts commit 0622b05.

Author: gaaclarke

build/darwin/ios_app.gni

@@ -851,8 +851,6 @@ FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStan
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/FlutterStandardCodec_Internal.h
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/flutter_codecs_unittest.mm
 FILE: ../../../flutter/shell/platform/darwin/common/framework/Source/flutter_standard_codec_unittest.mm
-FILE: ../../../flutter/shell/platform/darwin/ios/FlutterTestsInfo.plist
-FILE: ../../../flutter/shell/platform/darwin/ios/flutter_unittests.mm
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Flutter.podspec
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Headers/Flutter.h
 FILE: ../../../flutter/shell/platform/darwin/ios/framework/Headers/FlutterAppDelegate.h

ci/licenses_golden/licenses_flutter

@@ -5,7 +5,6 @@
 assert(is_ios)
 
 import("//build/config/ios/ios_sdk.gni")
-import("//flutter/build/darwin/ios_app.gni")
 import("//flutter/common/config.gni")
 import("//flutter/shell/gpu/gpu.gni")
 import("//flutter/shell/platform/darwin/common/framework_shared.gni")
@@ -331,29 +330,6 @@ shared_library("copy_and_verify_framework_headers") {
   ]
 }
 
-test_fixtures("flutter_tests_fixtures") {
-  fixtures = []
-}
-
-# Note: This currently isn't used, it might be removed.
-ios_app("FlutterTests") {
-  testonly = true
-
-  info_plist = "FlutterTestsInfo.plist"
-
-  sources = [
-    "flutter_unittests.mm",
-  ]
-
-  libs = [ "Foundation.framework" ]
-
-  deps = [
-    ":flutter_tests_fixtures",
-    "//flutter/runtime:libdart",
-    "//flutter/testing",
-  ]
-}
-
 group("flutter_framework") {
   deps = [
     ":copy_and_verify_framework_headers",