DO NOT MERGE Overloading createMessageTyped to accept a tag as an integer.

When building, some instances expect createMessageTyped to have the signature
(int, Class, long), while others expect (int, Class, int). Simply having
the former signature meant that builds expecting the latter would fail.

This is a cherrypick of change b2a9d4321578139677c146ce37eba5e27e8f5c79
from master.

Change-Id: Ib02dbf66173510f4edea32c7b43e82c1a7a38aa2

javanano/src/main/java/com/google/protobuf/nano/Extension.java

@@ -74,6 +74,19 @@ public class Extension<M extends ExtendableMessageNano<M>, T> {
     public static final int TYPE_SINT32   = InternalNano.TYPE_SINT32;
     public static final int TYPE_SINT64   = InternalNano.TYPE_SINT64;
 
+    /**
+     * Creates an {@code Extension} of the given message type and tag number.
+     * Should be used by the generated code only.
+     *
+     * @param type {@link #TYPE_MESSAGE} or {@link #TYPE_GROUP}
+     * @deprecated use {@link #createMessageTyped(int, Class, long)} instead.
+     */
+    @Deprecated
+    public static <M extends ExtendableMessageNano<M>, T extends MessageNano>
+            Extension<M, T> createMessageTyped(int type, Class<T> clazz, int tag) {
+        return new Extension<M, T>(type, clazz, tag, false);
+    }
+
     // Note: these create...() methods take a long for the tag parameter,
     // because tags are represented as unsigned ints, and these values exist
     // in generated code as long values. However, they can fit in 32-bits, so

javanano/src/main/java/com/google/protobuf/nano/Extension.java.rej

-diff a/javanano/src/main/java/com/google/protobuf/nano/Extension.java b/javanano/src/main/java/com/google/protobuf/nano/Extension.java	(rejected hunks)
-@@ -74,6 +74,11 @@ public class Extension<M extends ExtendableMessageNano<M>, T> {
-     public static final int TYPE_SINT32   = 17;
-     public static final int TYPE_SINT64   = 18;
- 
-+    // Note: these create...() methods take a long for the tag parameter,
-+    // because tags are represented as unsigned longs, and these values exist
-+    // in generated code as long values. However, they can fit in 32-bits, so
-+    // it's safe to cast them to int without loss of precision.
-+
-     /**
-      * Creates an {@code Extension} of the given message type and tag number.
-      * Should be used by the generated code only.