OSCrypt for POSIX uses libsecret to store a randomised encryption key.

components/os_crypt/BUILD.gn

Index: components/os_crypt/BUILD.gn
diff --git a/components/os_crypt/BUILD.gn b/components/os_crypt/BUILD.gn
index 6e37c63c8c280dead73a9d623ee963300ae0db4d..9c5000203efa2317126a254d0e7c359ee927b879 100644
--- a/components/os_crypt/BUILD.gn
+++ b/components/os_crypt/BUILD.gn
@@ -42,9 +42,15 @@ source_set("os_crypt") {
   }
 
   if (is_desktop_linux) {
+    sources -= [ "os_crypt_posix.cc" ]
     sources += [
-      "libsecret_util_posix.cc",
-      "libsecret_util_posix.h",
+      "key_storage_libsecret.cc",
+      "key_storage_libsecret.h",
+      "key_storage_linux.cc",
+      "key_storage_linux.h",
+      "libsecret_util_linux.cc",
+      "libsecret_util_linux.h",
+      "os_crypt_linux.cc",
     ]
     configs += [ "//build/config/linux:glib" ]
     deps += [ "//third_party/libsecret" ]
@@ -65,4 +71,14 @@ source_set("unit_tests") {
     "//crypto",
     "//testing/gtest",
   ]
+
+  if (is_desktop_linux) {
+    sources += [

[Lei Zhang, 2016/05/19 22:45:38]

Can we have components/components_tests.gyp follow the same logic? As is, the
GYP version does not exclude the mock.

[cfroussios, 2016/05/20 16:44:52]

In components/components_tests.gyp, the mock is in 'os_crypt_unittest_sources'.
Aren't all of those files supposed to be excluded?

+      "key_storage_mock.cc",
+      "key_storage_mock.h",
+      "os_crypt_util_linux_unittest.cc",
+    ]
+    deps += [ "//third_party/libsecret" ]
+    defines = [ "USE_LIBSECRET" ]
+  }
 }