Update from https://crrev.com/315085

This includes the switch to libc++ on Android.

Other fixes:

*) Add (dumb) impl of OrderingBarrier() to command buffer
*) "base/debug/trace_event.h" -> "base/trace_event/trace_event.h"
*) Added a few <cmath> includes to sky

Review URL: https://codereview.chromium.org/903273002
diff --git a/url/gurl.h b/url/gurl.h
index ef1e529..566fc5e 100644
--- a/url/gurl.h
+++ b/url/gurl.h
@@ -18,8 +18,8 @@
 
 class URL_EXPORT GURL {
  public:
-  typedef url::StdStringReplacements<std::string> Replacements;
-  typedef url::StdStringReplacements<base::string16> ReplacementsW;
+  typedef url::StringPieceReplacements<std::string> Replacements;
+  typedef url::StringPieceReplacements<base::string16> ReplacementsW;
 
   // Creates an empty, invalid URL.
   GURL();