Simplify capturing of base::JSONReader::Read() return value.

base::JSONReader::Read() returns a std::unique_ptr<Value>, which can
simply be captured into a std::unique_ptr<Value> variable instead of
calling .release() on the returned unique_ptr and constructing a
unique_ptr from the released raw pointer.

BUG=None
TEST=Run unit tests.

Change-Id: I6be2fb14676be31ae578afceda2410a4b5f6af5e
Reviewed-on: https://chromium-review.googlesource.com/438760
Commit-Ready: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
diff --git a/chromeos-dbus-bindings/generate_chromeos_dbus_bindings.cc b/chromeos-dbus-bindings/generate_chromeos_dbus_bindings.cc
index b22c141..361a38e 100644
--- a/chromeos-dbus-bindings/generate_chromeos_dbus_bindings.cc
+++ b/chromeos-dbus-bindings/generate_chromeos_dbus_bindings.cc
@@ -79,7 +79,7 @@
   if (!base::ReadFileToString(path, &contents))
     return false;
 
-  std::unique_ptr<base::Value> json{base::JSONReader::Read(contents).release()};
+  std::unique_ptr<base::Value> json = base::JSONReader::Read(contents);
   if (!json)
     return false;