Fixed Linux build with glib 2.40 (Ubuntu 14.04).

net/proxy/proxy_config_service_linux.cc

Index: net/proxy/proxy_config_service_linux.cc
diff --git a/net/proxy/proxy_config_service_linux.cc b/net/proxy/proxy_config_service_linux.cc
index a93567d1e00de5e4f327496667aa2e4a53be5fbf..0e65b72c12acc4f561873b9e8a252ec6b7cbbd70 100644
--- a/net/proxy/proxy_config_service_linux.cc
+++ b/net/proxy/proxy_config_service_linux.cc
@@ -4,6 +4,15 @@
 
 #include "net/proxy/proxy_config_service_linux.h"
 
+// glib >=2.40 deprecate g_settings_list_schemas in favor of
+// g_settings_schema_source_list_schemas. This function is not available on
+// earlier versions that we still need to support (specifically, 2.32), so
+// disable the warning.
+// TODO(mgiuca): Remove this suppression when we drop support for Ubuntu 13.10
+// (saucy) and earlier. Update the code to use
+// g_settings_schema_source_list_schemas instead.
+#define GLIB_DISABLE_DEPRECATION_WARNINGS
+
 #include <errno.h>
 #include <fcntl.h>
 #if defined(USE_GCONF)
@@ -39,9 +48,6 @@
 #include "url/url_canon.h"
 
 #if defined(USE_GIO)
-#if __clang__
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-#endif
 #include "library_loaders/libgio.h"
 #endif  // defined(USE_GIO)