Add testing/iossim/BUILD.gn to build iossim as host for iOS build.

testing/iossim/iossim.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <asl.h>
 #import <Foundation/Foundation.h>
 #include <libgen.h>
 #include <stdarg.h>
 #include <stdio.h>
 
@@ skipping 51 matching lines @@
 // is the PID of the process the message is about (as opposed to launchd's PID).
 #define ASL_KEY_REF_PID "RefPID"
 
 namespace {
 
 // Name of environment variables that control the user's home directory in the
 // simulator.
 const char* const kUserHomeEnvVariable = "CFFIXED_USER_HOME";
 const char* const kHomeEnvVariable = "HOME";
 
-// Device family codes for iPhone and iPad.
-const int kIPhoneFamily = 1;
-const int kIPadFamily = 2;

[Dirk Pranke, 2016/03/16 01:23:22]

Are these (and the constant on line 113) no longer needed?

[sdefresne, 2016/03/17 10:53:47]

Yeah, they cause compilation about unused const variables when building with gn
(not with gyp as they are build with 'chromium_code' set to 0). Since the
changes were minor, I chose to remove dead code instead of adding
-Wno-unused-const-variables to BUILD.gn config.

-
 // Max number of seconds to wait for the simulator session to start.
 // This timeout must allow time to start up iOS Simulator, install the app
 // and perform any other black magic that is encoded in the
 // iPhoneSimulatorRemoteClient framework to kick things off. Normal start up
 // time is only a couple seconds but machine load, disk caches, etc., can all
 // affect startup time in the wild so the timeout needs to be fairly generous.
 // If this timeout occurs iossim will likely exit with non-zero status; the
 // exception being if the app is invoked and completes execution before the
 // session is started (this case is handled in session:didStart:withError).
 const NSTimeInterval kDefaultSessionStartTimeoutSeconds = 30;
@@ skipping 17 matching lines @@
 
 const char* gToolName = "iossim";
 
 // Exit status codes.
 const int kExitSuccess = EXIT_SUCCESS;
 const int kExitFailure = EXIT_FAILURE;
 const int kExitInvalidArguments = 2;
 const int kExitInitializationFailure = 3;
 const int kExitAppFailedToStart = 4;
 const int kExitAppCrashed = 5;
-const int kExitUnsupportedXcodeVersion = 6;
 
 void LogError(NSString* format, ...) {
   va_list list;
   va_start(list, format);
 
   NSString* message =
       [[[NSString alloc] initWithFormat:format arguments:list] autorelease];
 
   fprintf(stderr, "%s: ERROR: %s\n", gToolName, [message UTF8String]);
   fflush(stderr);
@@ skipping 773 matching lines @@
              [error localizedDescription],
              [error domain], static_cast<long int>([error code]));
   }
 
   // Note that this code is only executed if the simulator fails to start
   // because once the main run loop is started, only the delegate calling
   // exit() will end the program.
   [pool drain];
   return kExitFailure;
 }