Debugger: Fix array dumping in corner cases

Don't try to use the compact method if we can't determine the
underlying format as we wouldn't know how to display the data
on the Creator side.

Change-Id: I985b9354c883da3a75bce1fe170b1f6cccc1dc21
Reviewed-by: David Schulz <david.schulz@digia.com>

share/qtcreator/debugger/gdbbridge.py

@@ -1468,13 +1468,14 @@ class Dumper(DumperBase):
         return None
 
     def tryPutArrayContents(self, typeobj, base, n):
-        if not self.isSimpleType(typeobj):
+        enc = self.simpleEncoding(typeobj)
+        if not enc:
             return False
         size = n * typeobj.sizeof;
         self.put('childtype="%s",' % typeobj)
         self.put('addrbase="0x%x",' % toInteger(base))
         self.put('addrstep="0x%x",' % toInteger(typeobj.sizeof))
-        self.put('arrayencoding="%s",' % self.simpleEncoding(typeobj))
+        self.put('arrayencoding="%s",' % enc)
         self.put('arraydata="')
         self.put(self.readMemory(base, size))
         self.put('",')