[Mac Fix-It] removed base::mac::AmIForeground function.

base/mac/mac_util.mm

Index: base/mac/mac_util.mm
diff --git a/base/mac/mac_util.mm b/base/mac/mac_util.mm
index d4b584debb78cd9f7a61eda786faa7a11bc2f13a..2f54b2799b5b01932b94fce98a63e5145ebae94b 100644
--- a/base/mac/mac_util.mm
+++ b/base/mac/mac_util.mm
@@ -218,26 +218,6 @@ void SwitchFullScreenModes(FullScreenMode from_mode, FullScreenMode to_mode) {
   SetUIMode();
 }
 
-bool AmIForeground() {
-  ProcessSerialNumber foreground_psn = { 0 };
-  OSErr err = GetFrontProcess(&foreground_psn);
-  if (err != noErr) {
-    OSSTATUS_DLOG(WARNING, err) << "GetFrontProcess";
-    return false;
-  }
-
-  ProcessSerialNumber my_psn = { 0, kCurrentProcess };
-
-  Boolean result = FALSE;
-  err = SameProcess(&foreground_psn, &my_psn, &result);
-  if (err != noErr) {
-    OSSTATUS_DLOG(WARNING, err) << "SameProcess";
-    return false;
-  }
-
-  return result;
-}
-
 bool SetFileBackupExclusion(const FilePath& file_path) {
   NSString* file_path_ns =
       [NSString stringWithUTF8String:file_path.value().c_str()];