Flipper | Stop exceptions being thrown for indicating that no Flipper desktop client is available

Summary:
Originally, Flipper would use exceptions for the control flow of determining if there's no desktop client available. It would catch an exception and then kick off another attempt. This is cool, but if you are debugging an application where Flipper is enabled, and you set a breakpoint to detect all thrown exceptions, then you'll see an exception thrown inside Flipper logic every couple of seconds. That makes it hard to debug what you're trying to do.

There's a workaround where you can simply open Flipper, but that's a bit annoying.

This diff changes the logic in Flipper to not use exceptions for the part of connection where it's doing the initial connect. We could apply this to `doCertificateExchange` as well, but that's actually an error there so I don't see the need to do it there as well.

Reviewed By: jknoxville

Differential Revision: D21016737

fbshipit-source-id: cbdfe2794b4d38a9e3b8304ebee845655bb26ae5

xplat/Flipper/FlipperConnectionManagerImpl.h

@@ -69,7 +69,7 @@ class FlipperConnectionManagerImpl : public FlipperConnectionManager {
 
   void startSync();
   void doCertificateExchange();
-  void connectSecurely();
+  bool connectSecurely();
   bool isCertificateExchangeNeeded();
   void requestSignedCertFromFlipper();
   bool isRunningInOwnThread();