Implemented B_CLOSE_ON_ESCAPE as mentioned on the mailing list.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@21308 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/Window.h

@@ -82,6 +82,7 @@ enum {
 	B_QUIT_ON_WINDOW_CLOSE		= 0x00100000,
 	B_SAME_POSITION_IN_ALL_WORKSPACES = 0x00200000,
 	B_AUTO_UPDATE_SIZE_LIMITS	= 0x00400000,
+	B_CLOSE_ON_ESCAPE			= 0x00800000
 };
 
 #define B_CURRENT_WORKSPACE	0

src/kits/interface/Window.cpp

@@ -3138,6 +3138,15 @@ BWindow::_HandleKeyDown(BMessage* event)
 		return true;
 	}
 
+	// Optionally close window when the escape key is pressed
+	if (key == B_ESCAPE && (Flags() & B_CLOSE_ON_ESCAPE) != 0) {
+		BMessage message(B_QUIT_REQUESTED);
+		message.AddBool("shortcut", true);
+
+		PostMessage(&message);
+		return true;
+	}
+	
 	// Handle shortcuts
 	if ((modifiers & B_COMMAND_KEY) != 0) {
 		// Command+q has been pressed, so, we will quit