Add default implementation for IDocument::fallbackSaveAs(Path|FileName)

The methods are only relevant for documents without a filePath, and
there was a mix of different irrelevant implementations present in
subclasses.

Change-Id: I4f57d306e5ddd913974cfe6ed0b4db062eb907a1
Reviewed-by: David Schulz <david.schulz@theqtcompany.com>

src/plugins/android/javaeditor.cpp

@@ -58,8 +58,6 @@ class JavaDocument : public TextEditor::TextDocument
 {
 public:
     JavaDocument();
-    QString fallbackSaveAsPath() const override;
-    QString fallbackSaveAsFileName() const override;
 };
 
 
@@ -70,17 +68,6 @@ JavaDocument::JavaDocument()
     setIndenter(new JavaIndenter);
 }
 
-QString JavaDocument::fallbackSaveAsPath() const
-{
-    return filePath().toFileInfo().absolutePath();
-}
-
-QString JavaDocument::fallbackSaveAsFileName() const
-{
-    return filePath().fileName();
-}
-
-
 //
 // JavaEditorFactory
 //