Fix the documentation and add Device.deviceName in sessions API.

chrome/browser/extensions/api/sessions/sessions_apitest.cc

Index: chrome/browser/extensions/api/sessions/sessions_apitest.cc
diff --git a/chrome/browser/extensions/api/sessions/sessions_apitest.cc b/chrome/browser/extensions/api/sessions/sessions_apitest.cc
index e8980ae0f615c7a1be939f9958f6e142afbed23c..cc208d22acc41d70e8295bf411b965d1d16fef9d 100644
--- a/chrome/browser/extensions/api/sessions/sessions_apitest.cc
+++ b/chrome/browser/extensions/api/sessions/sessions_apitest.cc
@@ -226,6 +226,7 @@ IN_PROC_BROWSER_TEST_F(ExtensionSessionsTest, GetDevices) {
   for (size_t i = 0; i < devices->GetSize(); ++i) {
     EXPECT_TRUE(devices->GetDictionary(i, &device));
     EXPECT_EQ(kSessionTags[i], utils::GetString(device, "info"));
+    EXPECT_EQ(kSessionTags[i], utils::GetString(device, "deviceName"));
     EXPECT_TRUE(device->GetList("sessions", &sessions));
     EXPECT_EQ(0u, sessions->GetSize());
   }
@@ -247,6 +248,7 @@ IN_PROC_BROWSER_TEST_F(ExtensionSessionsTest, GetDevicesMaxResults) {
   for (size_t i = 0; i < devices->GetSize(); ++i) {
     EXPECT_TRUE(devices->GetDictionary(i, &device));
     EXPECT_EQ(kSessionTags[i], utils::GetString(device, "info"));
+    EXPECT_EQ(kSessionTags[i], utils::GetString(device, "deviceName"));
     EXPECT_TRUE(device->GetList("sessions", &sessions));
     EXPECT_EQ(1u, sessions->GetSize());
   }