509710: Error message on every 'unknown file type' opening

Only log the error instead of opening a popup

Bug: 509710
Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=509710
diff --git a/org.eclipse.epp.mpc.ui/src/org/eclipse/epp/internal/mpc/ui/AskMarketPlaceForFileSupportStrategy.java b/org.eclipse.epp.mpc.ui/src/org/eclipse/epp/internal/mpc/ui/AskMarketPlaceForFileSupportStrategy.java
index dc9dd67..26f530e 100644
--- a/org.eclipse.epp.mpc.ui/src/org/eclipse/epp/internal/mpc/ui/AskMarketPlaceForFileSupportStrategy.java
+++ b/org.eclipse.epp.mpc.ui/src/org/eclipse/epp/internal/mpc/ui/AskMarketPlaceForFileSupportStrategy.java
@@ -75,8 +75,9 @@
 					ISearchResult searchResult = marketplaceService.tagged(fileExtensionTag, monitor);
 					nodes = searchResult.getNodes();
 				} catch (CoreException ex) {
-					return new Status(IStatus.ERROR,
-							MarketplaceClientUiPlugin.getInstance().getBundle().getSymbolicName(), ex.getMessage(), ex);
+					//Only log the error and return cancel. Otherwise user would be bothered with error dialog popups, e.g. when working offline
+					MarketplaceClientUi.error(ex);
+					return Status.CANCEL_STATUS;
 				}
 				if (nodes.isEmpty()) {
 					return Status.OK_STATUS;