update_engine: Update libchrome APIs to r405848

The new libchrome has been ported from Chromium and some APIs have
changed. Make necessary changes at call sites.

Notable changes from libchrome:
- base::Bind() now explicitly disallows captures in lambdas (which was
  never allowed in the style guide), so lambdas should now be written in
  a way that take the captures as parameters.

Bug: 29104761
Test: All tests in update_engine_unittest pass on dragonboard-eng build
Change-Id: Iec04c126630fd876114076e3cb10cf917c8817b0
diff --git a/common/http_fetcher_unittest.cc b/common/http_fetcher_unittest.cc
index 0dd6f84..6f3e480 100644
--- a/common/http_fetcher_unittest.cc
+++ b/common/http_fetcher_unittest.cc
@@ -847,7 +847,8 @@
   // Check that no other callback runs in the next two seconds. That would
   // indicate a leaked callback.
   bool timeout = false;
-  auto callback = base::Bind([&timeout]{ timeout = true;});
+  auto callback = base::Bind([](bool* timeout) { *timeout = true; },
+                             base::Unretained(&timeout));
   this->loop_.PostDelayedTask(FROM_HERE, callback,
                               base::TimeDelta::FromSeconds(2));
   EXPECT_TRUE(this->loop_.RunOnce(true));