Bug 145139 - Added null guard

When no adapter of type StandbyPart is available on the platform,
standByPart will be null. Signal failure then.

Change-Id: Ib25b3e74c26e207c524cbb0a333029e06ed09d84
Signed-off-by: Karsten Thoms <karsten.thoms@itemis.de>
diff --git a/org.eclipse.ui.intro/src/org/eclipse/ui/internal/intro/impl/model/url/IntroURL.java b/org.eclipse.ui.intro/src/org/eclipse/ui/internal/intro/impl/model/url/IntroURL.java
index 7a008e2..3b21a98 100644
--- a/org.eclipse.ui.intro/src/org/eclipse/ui/internal/intro/impl/model/url/IntroURL.java
+++ b/org.eclipse.ui.intro/src/org/eclipse/ui/internal/intro/impl/model/url/IntroURL.java
@@ -237,13 +237,9 @@
         StandbyPart standbyPart = introPart
             .getAdapter(StandbyPart.class);
 
-        boolean success = standbyPart.showContentPart(partId, input);
-        if (success)
-            return true;
-
-        // we do not have a valid partId or we failed to instantiate part or
-        // create the part content, empty part will be shown. Signal failure.
-        return false;
+        // We may not have a valid partId or we might fail to instantiate part or
+        // create the part content. An empty part will be shown. Signal failure.
+        return standbyPart != null && standbyPart.showContentPart(partId, input);
     }
 
     /**