GN updates to build base on iOS

base/process/process_handle_mac.cc

Index: base/process/process_handle_mac.cc
diff --git a/base/process/process_handle_mac.cc b/base/process/process_handle_mac.cc
index cbf0bc5c4393fb9d3e0100e21ec3514ac504657b..64a27875024fe4db63fe5d726831527d96ce5eaf 100644
--- a/base/process/process_handle_mac.cc
+++ b/base/process/process_handle_mac.cc
@@ -4,7 +4,10 @@
 
 #include "base/process/process_handle.h"
 
+#if !defined(OS_IOS)

[Nico, 2015/06/11 15:37:59]

base builds fine for ios in the gyp build. why do you need source changes?

[sdefresne, 2015/06/11 17:05:17]

I suspect you miss some system directory with gn. Can you compare command-line
when building with gn vs gyp? On my machine libproc.h is found in the SDK, so
the issue may be that -isysroot is incorrectly set with gn.

[Chinmay, 2015/06/11 17:44:36]

libproc.h is only present on the iPhone Simulator SDK. I am not sure if it was
present once for the device and subsequently removed. I have been scouring the
API changelogs but cant find any mention of the same. Sky builds use the iOS 8
SDK. I found a relevant Radar http://www.openradar.appspot.com/12934352. Looking
for libproc.h yields

```
➜  Xcode.app  find /Applications/Xcode.app | grep libproc.h$
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/include/libproc.h
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/libproc.h
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/usr/include/libproc.h

```

I just re-verified the sysroot flags too. They seem to be in order.

[sdefresne, 2015/06/11 17:54:32]

I've checked my gyp build and process_handle_mac.cc is not build when building
for iOS (neither for simulator nor device):

$ ninja -C out/Debug-iphoneos -v -n base|grep process_handle_mac
$ ninja -C out/Debug-iphonesimulator -v -n base|grep process_handle_mac

 #include <libproc.h>
+#endif
+
 #include <sys/sysctl.h>
 #include <sys/types.h>
 
@@ -25,6 +28,8 @@ ProcessId GetParentProcessId(ProcessHandle process) {
   return info.kp_eproc.e_ppid;
 }
 
+#if !defined(OS_IOS)
+
 FilePath GetProcessExecutablePath(ProcessHandle process) {
   char pathbuf[PROC_PIDPATHINFO_MAXSIZE];
   if (!proc_pidpath(process, pathbuf, sizeof(pathbuf)))
@@ -33,4 +38,6 @@ FilePath GetProcessExecutablePath(ProcessHandle process) {
   return FilePath(pathbuf);
 }
 
+#endif
+
 }  // namespace base