Add libc++ and libc++abi to third-party.

DEPS

Index: DEPS
===================================================================
--- DEPS	(revision 239464)
+++ DEPS	(working copy)
@@ -17,6 +17,7 @@
   # If you do not know, use the full path while defining your new deps entry.
   "googlecode_url": "http://%s.googlecode.com/svn",
   "sourceforge_url": "http://svn.code.sf.net/p/%(repo)s/code",
+  "llvm_url": "http://llvm.org/svn/llvm-project",
   "webkit_trunk": "http://src.chromium.org/blink/trunk",
   "nacl_trunk": "http://src.chromium.org/native_client/trunk",
   "webkit_revision": "163292",
@@ -112,6 +113,12 @@
   "src/third_party/leveldatabase/src":
     (Var("googlecode_url") % "leveldb") + "/trunk@77",
 
+  "src/third_party/libc++/trunk":
+    Var("llvm_url") + "/libcxx/trunk",

[Alexander Potapenko, 2013/12/09 13:52:56]

We must pin fixed versions of libc++ and libc++abi.

[alextaran1, 2013/12/10 13:49:30]

Done.

+  
+  "src/third_party/libc++abi/trunk":
+    Var("llvm_url") + "/libcxxabi/trunk",
+
   "src/third_party/snappy/src":
     (Var("googlecode_url") % "snappy") + "/trunk@80",