Return error if isProtectedDataAvailable = false

Addresses issue #72 where SecItemCOpyMatching doesn't return data and
doesn't give an error when the protected files are not yet
available. This will now give an error instead of empty results,
allowing the caller to retry after some delay.

Author: Kelly Campbell

ios/RNSensitiveInfo/RNSensitiveInfo.m

@@ -215,7 +215,15 @@ - (NSString *)messageForError:(NSError *)error
         return;
     }
 
-    [self getItemWithQuery:query resolver:resolve rejecter:reject];
+    dispatch_async(dispatch_get_main_queue(), ^{
+        if (UIApplication.sharedApplication.protectedDataAvailable) {
+            [self getItemWithQuery:query resolver:resolve rejecter:reject];
+        } else {
+            // TODO: could change to instead of erroring out, listen for protectedDataDidBecomeAvailable and call getItemWIthQuery when it does
+            // Experiment for now by returning an error and let the js side retry
+            reject(@"protected_data_unavailable", @"Protected data not available yet. Retry operation", nil);
+        }
+    });
 }
 
 - (void)getItemWithQuery:(NSDictionary *)query resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject {