add 'From': GClientKeywords.FromImpl to autoroll

Take change from webrtc into libyuv autoroll
BUG=libyuv:716
TEST=tools_libyuv/autoroller/roll_deps.py
TBR=kjellander@chromium.org

Change-Id: I81b1eed114b982e336f2e209d7d825094e584295
Reviewed-on: https://chromium-review.googlesource.com/596472Reviewed-by: Frank Barchard <fbarchard@google.com>
Commit-Queue: Frank Barchard <fbarchard@google.com>

tools_libyuv/autoroller/roll_deps.py

@@ -66,6 +66,7 @@ def ParseDepsDict(deps_content):
   local_scope = {}
   var = GClientKeywords.VarImpl({}, local_scope)
   global_scope = {
+    'From': GClientKeywords.FromImpl,
     'Var': var.Lookup,
     'deps_os': {},
   }