HaikuDepot: Set package state when loading single package

Without this, even installed packages still get an "Install" button.

Fixes #14821.

This was implemented by adding BPackageRoster::IsPackageActive. I decided to
have this take a location since GetActivePackages also did, but as noted in my
TODO comment, I think this is awkward.

It would also be nice to show the user they have a different version of a
particular package, but that would require some changes to IsPackageActive.

Change-Id: Iab0d35eb6b671a17711b0214b15164d296927e5a
Reviewed-on: https://review.haiku-os.org/c/1694
Reviewed-by: Stephan Aßmus <[email protected]>

headers/os/package/PackageRoster.h

@@ -32,6 +32,7 @@ class BInstallationLocationInfo;
 class BPackageInfoSet;
 class BRepositoryCache;
 class BRepositoryConfig;
+class BPackageInfo;
 
 
 // watchable events
@@ -87,6 +88,10 @@ public:
 									BPackageInstallationLocation location,
 									BPackageInfoSet& packageInfos);
 
+			status_t			IsPackageActive(
+									BPackageInstallationLocation location,
+									const BPackageInfo info, bool* active);
+
 			status_t			StartWatching(const BMessenger& target,
 									uint32 eventMask);
 			status_t			StopWatching(const BMessenger& target);