AU: Ensure update_engine_client get proxy retries are spaced out in time.

Hopefully, this will reduce test flakyness. It seems that last time the test
failed all 4 tries happened within a one-second timeframe.

Also, fix GError object memory leaks throughout the code.

BUG=chromium-os:21351
TEST=unit tests, tested on VM

Change-Id: If0bc5d5767d12f3396d0fcb46f3e04ed6d7dfd5c
Reviewed-on: http://gerrit.chromium.org/gerrit/8862
Commit-Ready: Darin Petkov <petkov@chromium.org>
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/chrome_browser_proxy_resolver.cc b/chrome_browser_proxy_resolver.cc
index 8c35afb..7b0bdc6 100644
--- a/chrome_browser_proxy_resolver.cc
+++ b/chrome_browser_proxy_resolver.cc
@@ -60,8 +60,8 @@
                                                  kLibCrosServiceInterface,
                                                  &error);
   if (!proxy) {
-    LOG(ERROR) << "Error getting dbus proxy for "
-               << kLibCrosServiceName << ": " << utils::GetGErrorMessage(error);
+    LOG(ERROR) << "Error getting dbus proxy for " << kLibCrosServiceName << ": "
+               << utils::GetAndFreeGError(&error);
     return NULL;
   }
   return proxy;
@@ -137,7 +137,7 @@
           G_TYPE_STRING, kLibCrosProxyResolveName,
           G_TYPE_INVALID, G_TYPE_INVALID)) {
     LOG(WARNING) << "dbus_g_proxy_call failed: "
-                 << utils::GetGErrorMessage(error)
+                 << utils::GetAndFreeGError(&error)
                  << " Continuing with no proxy.";
     timeout = 0;
   }