Fix file not dirty while its content changed on the hard drive.

Set buffer state to dirty when the file on the file system has changed but the user decided to not reload it in Notepad++.

Fixes #3246, closes #3499

PowerEditor/src/Notepad_plus.cpp

@@ -5018,7 +5018,12 @@ void Notepad_plus::notifyBufferChanged(Buffer * buffer, int mask)
 
 					// Then we ask user to update
 					if (doReloadOrNot(buffer->getFullPathName(), buffer->isDirty()) != IDYES)
+					{
+						// Since the file content has changed but the user doesn't want to reload it, set state to dirty
+						buffer->setDirty(true);
+
 						break;	//abort
+					}
 				}
 				// Set _isLoadedDirty false so when the document clean state is reached the icon will be set to blue
 				buffer->setLoadedDirty(false);