Update from https://crrev.com/333737

* Cherrypick crrev.com/333293 (freetype -> freetype-android).
* Update mojo/go/go.py to use android-16 (NDK API level 16), which is
  4.1 (first Jelly Bean). Chromium dropped support for 14.
* TODO (separately): also update tools/go/upload.py and upload new
  binaries?
* Roll android_tools (to match Chromium).
* Small fixes to match //base changes: base::ObserverList, TraceConfig,
  ThreadTicks, etc.
* Restore build/ls.py (and add it to the list of files to not roll).
* Remove the dependency on third_party/instrumented_libraries.
* Add "enable_topchrome_md = false" to build/config/ui.gni.
* Add build/config/ui.gni to files_not_to_roll in
  update_from_chromium.py. (We should probably get rid of the use_glib
  variable/argument, and others as well.)
* Remove mojo/tools/roll/{roll_network_service.py,
  roll_network_service_patches/network_service.patch}. These are for
  rolling from Chromium, whereas we now have/use monet.
* Roll buildtools (to match Chromium).
* Modify sanitizer gn/gni files to make it work (patch included).
  (Maybe the patch even works -- I haven't checked.)

TBR=rockot@chromium.org,jamesr@chromium.org,rogulenko@google.com

Review URL: https://codereview.chromium.org/1180693002.
diff --git a/base/json/string_escape.cc b/base/json/string_escape.cc
index a3b0735..469f9f9 100644
--- a/base/json/string_escape.cc
+++ b/base/json/string_escape.cc
@@ -135,7 +135,7 @@
     dest.push_back('"');
 
   for (StringPiece::const_iterator it = str.begin(); it != str.end(); ++it) {
-    ToUnsigned<StringPiece::value_type>::Unsigned c = *it;
+    unsigned char c = *it;
     if (EscapeSpecialCodePoint(c, &dest))
       continue;