Bug 1553781: When the remote service finds an instance to remote to it doesn't clean up the startup lock. r=glandium

This fixes the issue in a few redundant ways:
* nsProfileLock is made to properly clean itself up when destroyed.
* nsRemoteService makes sure the unlock when destroyed.
* nsAppRunner unlocks when a remote client has been found.

Differential Revision: https://phabricator.services.mozilla.com/D32360

--HG--
extra : moz-landing-system : lando

toolkit/components/remote/nsRemoteService.cpp

@@ -77,10 +77,10 @@ void nsRemoteService::LockStartup() {
 }
 
 void nsRemoteService::UnlockStartup() {
-  mRemoteLock.Unlock();
-  mRemoteLock.Cleanup();
-
   if (mRemoteLockDir) {
+    mRemoteLock.Unlock();
+    mRemoteLock.Cleanup();
+
     mRemoteLockDir->Remove(false);
     mRemoteLockDir = nullptr;
   }
@@ -174,7 +174,10 @@ void nsRemoteService::StartupServer() {
 
 void nsRemoteService::ShutdownServer() { mRemoteServer = nullptr; }
 
-nsRemoteService::~nsRemoteService() { ShutdownServer(); }
+nsRemoteService::~nsRemoteService() {
+  UnlockStartup();
+  ShutdownServer();
+}
 
 NS_IMETHODIMP
 nsRemoteService::Observe(nsISupports* aSubject, const char* aTopic,

toolkit/profile/nsProfileLock.cpp

@@ -84,7 +84,11 @@ nsProfileLock& nsProfileLock::operator=(nsProfileLock& rhs) {
   return *this;
 }
 
-nsProfileLock::~nsProfileLock() { Unlock(); }
+nsProfileLock::~nsProfileLock() {
+  Unlock();
+  // Note that we don't clean up by default here so on next startup we know when
+  // the profile was last used based on the modification time of the lock file.
+}
 
 #if defined(XP_UNIX)
 
@@ -566,8 +570,14 @@ nsresult nsProfileLock::Unlock(bool aFatalSignal) {
 }
 
 nsresult nsProfileLock::Cleanup() {
+  if (mHaveLock) {
+    return NS_ERROR_FILE_IS_LOCKED;
+  }
+
   if (mLockFile) {
-    return mLockFile->Remove(false);
+    nsresult rv = mLockFile->Remove(false);
+    NS_ENSURE_SUCCESS(rv, rv);
+    mLockFile = nullptr;
   }
 
   return NS_OK;

toolkit/xre/nsAppRunner.cpp

@@ -4000,9 +4000,11 @@ int XREMain::XRE_mainStartup(bool* aExitFlag) {
       RemoteResult rr = mRemoteService->StartClient(desktopStartupIDPtr);
       if (rr == REMOTE_FOUND) {
         *aExitFlag = true;
+        mRemoteService->UnlockStartup();
         return 0;
       }
       if (rr == REMOTE_ARG_BAD) {
+        mRemoteService->UnlockStartup();
         return 1;
       }
     }