Set the QSettings path to a config-subdirectory.

QWebInspector uses QSettings to save its GUI-settings. However, the default
path for QSettings is ~/.config/qutebrowser/qutebrowser.conf which overwrites
our own config file.

This fixes one part of #515.

qutebrowser/config/config.py

@@ -32,7 +32,8 @@ import configparser
 import collections
 import collections.abc
 
-from PyQt5.QtCore import pyqtSignal, pyqtSlot, QObject, QStandardPaths, QUrl
+from PyQt5.QtCore import (pyqtSignal, pyqtSlot, QObject, QStandardPaths, QUrl,
+                          QSettings)
 from PyQt5.QtWidgets import QMessageBox
 
 from qutebrowser.config import configdata, configexc, textwrapper
@@ -205,6 +206,18 @@ def _init_misc(args):
     save_manager.add_saveable('command-history', command_history.save,
                               command_history.changed)
 
+    # Set the QSettings path to something like
+    # ~/.config/qutebrowser/qsettings/qutebrowser/qutebrowser.conf so it
+    # doesn't overwrite our config.
+    #
+    # This fixes one of the corruption issues here:
+    # https://github.com/The-Compiler/qutebrowser/issues/515
+
+    config_path = standarddir.get(QStandardPaths.ConfigLocation, args)
+    path = os.path.join(config_path, 'qsettings')
+    for fmt in (QSettings.NativeFormat, QSettings.IniFormat):
+        QSettings.setPath(fmt, QSettings.UserScope, path)
+
 
 def init(args):
     """Initialize the config.