[iOS] Clean up xcode_test_application_name usages in XcodeWriter.

https://chromium-review.googlesource.com/c/566592 This CL uses
test_application_name in BUILD files to specify the relationship
between XCTest target and corresponding test application target.
So, clean up the code in XcodeWriter.

Bug: 741147, 709289
Change-Id: I4ce05f98c96bb05cf7cba1d1b67651996343c995
Reviewed-on: https://chromium-review.googlesource.com/614748
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#494791}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 82cd07781b74cde019826c73e9706f9c113902b7
diff --git a/tools/gn/xcode_writer.cc b/tools/gn/xcode_writer.cc
index 28ea355..0b19448 100644
--- a/tools/gn/xcode_writer.cc
+++ b/tools/gn/xcode_writer.cc
@@ -132,21 +132,12 @@
                         base::CompareCase::SENSITIVE);
 }
 
-// TODO(crbug.com/741147) Remove this function and switch to use
-// test_application_name once the bug is fixed and GN has rolled past it.
-const Target* FindXCTestApplicationTarget(
-    const Target* xctest_module_target,
+const Target* FindApplicationTargetByName(
+    const std::string& target_name,
     const std::vector<const Target*>& targets) {
-  DCHECK(IsXCTestModuleTarget(xctest_module_target));
-  DCHECK(base::EndsWith(xctest_module_target->label().name(),
-                        kXCTestModuleTargetNamePostfix,
-                        base::CompareCase::SENSITIVE));
-  std::string application_target_name =
-      xctest_module_target->label().name().substr(
-          0, xctest_module_target->label().name().size() -
-                 strlen(kXCTestModuleTargetNamePostfix));
   for (const Target* target : targets) {
-    if (target->label().name() == application_target_name) {
+    if (target->label().name() == target_name) {
+      DCHECK(IsApplicationTarget(target));
       return target;
     }
   }
@@ -177,8 +168,8 @@
     if (!IsXCTestModuleTarget(target))
       continue;
 
-    const Target* test_application_target =
-        FindXCTestApplicationTarget(target, targets);
+    const Target* test_application_target = FindApplicationTargetByName(
+        target->bundle_data().xcode_test_application_name(), targets);
     const PBXTarget* test_application_pbxtarget =
         bundle_target_to_pbxtarget.at(test_application_target);
     PBXTarget* module_pbxtarget = bundle_target_to_pbxtarget.at(target);
@@ -560,8 +551,8 @@
           continue;
 
         // For XCTest, test files are compiled into the application bundle.
-        const Target* test_application_target =
-            FindXCTestApplicationTarget(target, targets);
+        const Target* test_application_target = FindApplicationTargetByName(
+            target->bundle_data().xcode_test_application_name(), targets);
         SearchXCTestFilesForTarget(test_application_target,
                                    &xctest_files_per_target);
         const Target::FileList& xctest_file_list =