enable shared lib support in linux for lua

R=bungeman@google.com, reed@google.com

Review URL: https://codereview.chromium.org/16099014

git-svn-id: http://skia.googlecode.com/svn/trunk@9703 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/utils/SkLua.cpp b/src/utils/SkLua.cpp
index aabb236..296229b 100644
--- a/src/utils/SkLua.cpp
+++ b/src/utils/SkLua.cpp
@@ -949,3 +949,8 @@
     REG_CLASS(L, SkRRect);
     REG_CLASS(L, SkTypeface);
 }
+
+extern "C" int luaopen_skia(lua_State* L) {
+    SkLua::Load(L);
+    return 0;
+}