Created web::UserAgentType.

ios/web/public/user_agent.h

Index: ios/web/public/user_agent.h
diff --git a/ios/web/public/user_agent.h b/ios/web/public/user_agent.h
index 627875e8153cdfef5be06bc8037b2cf5a12956ae..55214bc0eee8d28229f558c58d7a6a42246063ad 100644
--- a/ios/web/public/user_agent.h
+++ b/ios/web/public/user_agent.h
@@ -9,6 +9,25 @@
 
 namespace web {
 
+// Enum type specifying a user agent's type.
+enum class UserAgentType : short {
+  // Used for pages that are generated for app-specific URLs.
+  NONE = 0,
+
+  // The default user agent type.  Used to specify a mobile browser user agent.
+  MOBILE,
+
+  // Used when requesting the desktop version of a page.
+  DESKTOP
+};
+
+// Returns a string representation of |type|.
+std::string GetUserAgentTypeDescription(UserAgentType type);

[Eugene But (OOO till 7-30), 2017/02/25 01:51:52]

Could you please add tests for these.

EXPECT_EQ(NONE,
GetUserAgentTypeWithDescription(GetUserAgentTypeDescription(NONE)))
etc...

[kkhorimoto, 2017/02/27 23:29:04]

Done.

+
+// Returns a UserAgentType with the given description.  If |description| doesn't
+// correspond with a UserAgentType, UserAgentType::NONE will be returned.
+UserAgentType GetUserAgentTypeWithDescription(const std::string& description);
+
 // Returns the os cpu info portion for a user agent.
 std::string BuildOSCpuInfo();