Avoid use of raw types.

JDT's rules for raw types do not match javac's, so it issues a compile error.
Fixes #2082
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=96216812

guava/src/com/google/common/collect/ImmutableMap.java

@@ -280,7 +280,9 @@ public static <K, V> ImmutableMap<K, V> copyOf(Map<? extends K, ? extends V> map
         return kvMap;
       }
     } else if (map instanceof EnumMap) {
-      return copyOfEnumMapUnsafe(map);
+      @SuppressWarnings("unchecked") // safe since map is not writable
+      ImmutableMap<K, V> kvMap = (ImmutableMap<K, V>) copyOfEnumMap((EnumMap<?, ?>) map);
+      return kvMap;
     }
     return copyOf(map.entrySet());
   }
@@ -313,12 +315,6 @@ public static <K, V> ImmutableMap<K, V> copyOf(
     }
   }
 
-  // If the map is an EnumMap, it must have key type K for some <K extends Enum<K>>.
-  @SuppressWarnings({"unchecked", "rawtypes"})
-  private static <K, V> ImmutableMap<K, V> copyOfEnumMapUnsafe(Map<? extends K, ? extends V> map) {
-    return copyOfEnumMap((EnumMap) map);
-  }
-
   private static <K extends Enum<K>, V> ImmutableMap<K, V> copyOfEnumMap(
       EnumMap<K, ? extends V> original) {
     EnumMap<K, V> copy = new EnumMap<K, V>(original);