[Proximity Auth] Create one ProximityAuthClient per profile, rather than one global one.

chrome/browser/extensions/api/screenlock_private/screenlock_private_apitest.cc

Index: chrome/browser/extensions/api/screenlock_private/screenlock_private_apitest.cc
diff --git a/chrome/browser/extensions/api/screenlock_private/screenlock_private_apitest.cc b/chrome/browser/extensions/api/screenlock_private/screenlock_private_apitest.cc
index d1fcba8f0a3c48d3fdbe48ddbd578c6d5acbbc00..42ce4fd2c8d73410680f306d2b5a2af755554d48 100644
--- a/chrome/browser/extensions/api/screenlock_private/screenlock_private_apitest.cc
+++ b/chrome/browser/extensions/api/screenlock_private/screenlock_private_apitest.cc
@@ -95,6 +95,9 @@ class ScreenlockPrivateApiTest : public ExtensionApiTest,
   DISALLOW_COPY_AND_ASSIGN(ScreenlockPrivateApiTest);
 };
 
+// Locking is currently implemented only on ChromeOS.
+#if defined(OS_CHROMEOS)
+
 // Time out under MSan. http://crbug.com/478091
 // Flaky under LSan on ChromeOS. http://crbug.com/482002
 #if defined(MEMORY_SANITIZER) || defined(LEAK_SANITIZER) && defined(OS_CHROMEOS)
@@ -113,4 +116,6 @@ IN_PROC_BROWSER_TEST_F(ScreenlockPrivateApiTest, MAYBE_AuthType) {
   RunTest("screenlock_private/auth_type");
 }
 
+#endif  // defined(OS_CHROMEOS)
+
 }  // namespace extensions