Ensure crash reports will be uploaded on the Mac.

Regression from Breakpad r842 (Chromium r103778) - browser crash reports were
uploaded, but renderer crash reports were not. Messages such as these may have
been logged:

com.apple.launchd.peruser.x[y] could not lookup DNS configuration info
service: (ipc/send) invalid destination port
com.apple.launchd.peruser.x[y] Breakpad Reporter: Send Error: Error
Domain=NSURLErrorDomain Code=-1009 UserInfo=z "This computer’s Internet
connection appears to be offline." Underlying Error=(Error
Domain=kCFErrorDomainCFNetwork Code=-1009 UserInfo=w "This computer’s Internet
connection appears to be offline.")

When OnDemandServer establishes the bootstrap subset, it will now register the
parent bootstrap port in the subset namespace so that the Inspector can
recover this port and switch to it. The Sender, launched by the Inspector,
relies on the bootstrap port being set properly.

BUG=chromium:99252
TEST=All test cases from Chromium r103778 (bug chromium:28547) plus:
     about:crash should generate a crash report which should be uploaded,
     provided that throttling is not in effect. Remove or edit
     ~/Library/Preferences/com.Breakpad.crash_report_sender.plist to defeat
     throttling. Also verify that about:inducebrowsercrashforrealz works.
Review URL: http://breakpad.appspot.com/307001

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@843 4c0a9323-5329-0410-9bdc-e9ce6186880e

src/client/mac/Framework/OnDemandServer.mm

@@ -86,6 +86,21 @@ kern_return_t OnDemandServer::Initialize(const char *server_command,
     return kr;
   }
 
+  // The inspector will be invoked with its bootstrap port set to the subset,
+  // but the sender will need access to the original bootstrap port. Although
+  // the original port is the subset's parent, bootstrap_parent can't be used
+  // because it requires extra privileges. Stash the original bootstrap port
+  // in the subset by registering it under a known name. The inspector will
+  // recover this port and set it as its own bootstrap port in Inspector.mm
+  // Inspector::ResetBootstrapPort.
+  kr = bootstrap_register(bootstrap_subset_port,
+                          const_cast<char*>("BootstrapParentPort"),
+                          bootstrap_port);
+  if (kr != KERN_SUCCESS) {
+    PRINT_BOOTSTRAP_RESULT(kr, "bootstrap_register(): ");
+    return kr;
+  }
+
   kr = bootstrap_create_server(bootstrap_subset_port,
                                const_cast<char*>(server_command),
                                geteuid(),       // server uid