fix indentation (dotnet#1549)

Author: mairaw

xml/System.Collections.ObjectModel/ReadOnlyDictionary`2.xml

@@ -490,13 +490,13 @@
         <exception cref="T:System.ArgumentException">
           <paramref name="array" /> is multidimensional.
 
-              -or-
+-or-
 
-              The number of elements in the source dictionary is greater than the available space from <paramref name="arrayIndex" /> to the end of the destination <paramref name="array" />.
+The number of elements in the source dictionary is greater than the available space from <paramref name="arrayIndex" /> to the end of the destination <paramref name="array" />.
 
-              -or-
+-or-
 
-              Type <paramref name="T" /> cannot be cast automatically to the type of the destination <paramref name="array" />.</exception>
+Type <paramref name="T" /> cannot be cast automatically to the type of the destination <paramref name="array" />.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.ICollection&lt;System.Collections.Generic.KeyValuePair&lt;TKey,TValue&gt;&gt;.IsReadOnly">
@@ -1569,4 +1569,4 @@
       </Docs>
     </Member>
   </Members>
-</Type>
+</Type>