Fix makefile parsing when chromium_org isn't checked out.

Some branches don't have external/chromium_org checked out but do
include frameworks/webview to get the null WebView implementation. Fix
the makefile so that it doesn't try to include the nonexistent in this case.

Change-Id: I573128973a92093da8ac0ce0c5cfa6df6af5255b
1 file changed
tree: 12f0d8e23301a243fb49ec912156905cd74c0ad5
  2. chromium/
  3. nullwebview/