BWindow & WebPostive: Move TextView detection code

... from WebPositive to BWindow. This way every window will detect
Command+Arrows and send them to BTextView if a BTextView has focus
instead of just WebPositive.

https://www.freelists.org/post/haiku-development/Wordwise-jumping-with-CTRL-in-BTextView

This trick doesn't work in Vision though...

Fixes #9913

src/apps/webpositive/BrowserWindow.cpp

@@ -707,21 +707,7 @@ BrowserWindow::DispatchMessage(BMessage* message, BHandler* target)
 	if ((message->what == B_KEY_DOWN || message->what == B_UNMAPPED_KEY_DOWN)
 		&& message->FindString("bytes", &bytes) == B_OK
 		&& message->FindInt32("modifiers", &modifierKeys) == B_OK) {
-		modifierKeys = (int32)((uint32)modifierKeys & kModifiers);
+		if (bytes[0] == B_FUNCTION_KEY) {
-		BTextView* textView = dynamic_cast<BTextView*>(CurrentFocus());
-		if (bytes[0] == B_LEFT_ARROW && modifierKeys == B_COMMAND_KEY) {
-			if (textView != NULL)
-				textView->KeyDown(bytes, modifierKeys);
-			else
-				PostMessage(GO_BACK);
-			return;
-		} else if (bytes[0] == B_RIGHT_ARROW && modifierKeys == B_COMMAND_KEY) {
-			if (textView != NULL)
-				textView->KeyDown(bytes, modifierKeys);
-			else
-				PostMessage(GO_FORWARD);
-			return;
-		} else if (bytes[0] == B_FUNCTION_KEY) {
 			// Some function key Firefox compatibility
 			int32 key;
 			if (message->FindInt32("key", &key) == B_OK) {

src/kits/interface/Window.cpp

@@ -3803,6 +3803,17 @@ BWindow::_HandleKeyDown(BMessage* event)
 			return true;
 		}
 
+		// Send Command+Left and Command+Right to textview if it has focus
+		if (key == B_LEFT_ARROW || key == B_RIGHT_ARROW) {
+			// check key before doing expensive dynamic_cast
+			BTextView* textView = dynamic_cast<BTextView*>(CurrentFocus());
+			if (textView != NULL) {
+				textView->KeyDown(bytes, modifiers);
+				// eat the event
+				return true;
+			}
+		}
+
 		// Pretend that the user opened a menu, to give the subclass a
 		// chance to update it's menus. This may install new shortcuts,
 		// which is why we have to call it here, before trying to find