Address remaining scoped storage regressions

- Accelerate common path used to check the storage scope for a given path
- Update the logic for the `get_as_text()` method - previous logic loads the content of a text file one byte at a time

platform/android/file_access_filesystem_jandroid.h

@@ -73,6 +73,7 @@ public:
 	virtual bool eof_reached() const override; ///< reading passed EOF
 
 	virtual uint8_t get_8() const override; ///< get a byte
+	virtual String get_line() const override; ///< get a line
 	virtual uint64_t get_buffer(uint8_t *p_dst, uint64_t p_length) const override;
 
 	virtual Error get_error() const override; ///< get last error