Alpha 1.0.1: resize chats list with mouse press-and-drag.

Also fixed drag-n-drop images from Firefox in Windows.
Also some additional colors added to themes palette:
HistoryToDown button now has separate colors.
Windows title bar and buttons have separate active/inactive colors.

Telegram/SourceFiles/structs.h

@@ -366,8 +366,6 @@ private:
 
 };
 
-static const uint64 UserNoAccess = 0xFFFFFFFFFFFFFFFFULL;
-
 class BotCommand {
 public:
 	BotCommand(const QString &command, const QString &description) : command(command), _description(description) {
@@ -407,7 +405,6 @@ struct BotInfo {
 class PhotoData;
 class UserData : public PeerData {
 public:
-
 	UserData(const PeerId &id) : PeerData(id) {
 	}
 	void setPhoto(const MTPUserProfilePhoto &photo);
@@ -432,8 +429,14 @@ public:
 	bool isBotInlineGeo() const {
 		return flags & MTPDuser::Flag::f_bot_inline_geo;
 	}
+	bool isInaccessible() const {
+		return (access == NoAccess);
+	}
+	void setIsInaccessible() {
+		access = NoAccess;
+	}
 	bool canWrite() const {
-		return access != UserNoAccess;
+		return !isInaccessible();
 	}
 	bool isContact() const {
 		return (contact > 0);
@@ -507,6 +510,8 @@ private:
 	BlockStatus _blockStatus = BlockStatus::Unknown;
 	int _commonChatsCount = 0;
 
+	static constexpr const uint64 NoAccess = 0xFFFFFFFFFFFFFFFFULL;
+
 };
 
 class ChatData : public PeerData {