Move inline som functions ScopedDBusError into a .cc file

dbus::ScopedDBusError has inline constructor/destructor and
is_set() method that call into libdbus-1. By placing these
function calls in a header file, we add implicit link dependency
on components that need to use ScopedDBusError. If we move
them out to a .cc file, the dependency will be localized to
libchrome.

BUG=chromium:416628
TEST=dbus_unittests pass

Review URL: https://codereview.chromium.org/592793004

Cr-Commit-Position: refs/heads/master@{#296478}

dbus/BUILD.gn

@@ -25,6 +25,7 @@ component("dbus") {
     "object_proxy.h",
     "property.cc",
     "property.h",
+    "scoped_dbus_error.cc",
     "scoped_dbus_error.h",
     "string_util.cc",
     "string_util.h",

dbus/dbus.gyp

@@ -41,6 +41,7 @@
         'object_proxy.h',
         'property.cc',
         'property.h',
+        'scoped_dbus_error.cc',
         'scoped_dbus_error.h',
         'string_util.cc',
         'string_util.h',

dbus/scoped_dbus_error.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "dbus/scoped_dbus_error.h"
+
+namespace dbus {
+
+ScopedDBusError::ScopedDBusError() {
+  dbus_error_init(&error_);
+}
+
+ScopedDBusError::~ScopedDBusError() {
+  dbus_error_free(&error_);
+}
+
+bool ScopedDBusError::is_set() const {
+  return dbus_error_is_set(&error_);
+}
+
+}  // namespace dbus

dbus/scoped_dbus_error.h

@@ -7,21 +7,20 @@
 
 #include <dbus/dbus.h>
 
+#include "dbus/dbus_export.h"
+
 namespace dbus {
 
 // Utility class to ensure that DBusError is freed.
-class ScopedDBusError {
+class CHROME_DBUS_EXPORT ScopedDBusError {
  public:
-  ScopedDBusError() {
-    dbus_error_init(&error_);
-  }
-
-  ~ScopedDBusError() {
-    dbus_error_free(&error_);
-  }
+  // Do not inline methods that call dbus_error_xxx() functions.
+  // See http://crbug.com/416628
+  ScopedDBusError();
+  ~ScopedDBusError();
 
   DBusError* get() { return &error_; }
-  bool is_set() const { return dbus_error_is_set(&error_); }
+  bool is_set() const;
   const char* name() { return error_.name; }
   const char* message() { return error_.message; }