* Only create CodeContext instances for "real" editors windows, but
not e.g. shell or output windows.
* Remove configuration update Tk event fired every second, by having
the editor window ask its code context widget to update when
necessary, i.e. upon font or highlighting updates.
* When code context isn't being shown, avoid having a Tk event fired
every 100ms to check whether the code context needs to be updated.
* Use the editor window's getlineno() method where applicable.
* Update font of the code context widget before the main text widget
Part 3 of 3, continuing PR #7689. This covers 14 idlelib modules and their tests,
rpc to zoomheight except for run (already done) and tooltip (being done separately).
About 10 IDLE features were implemented as supposedly optional
extensions. Their different behavior could be confusing or worse for
users and not good for maintenance. Hence the conversion.
The main difference for users is that user configurable key bindings
for builtin features are now handled uniformly. Now, editing a binding
in a keyset only affects its value in the keyset. All bindings are
defined together in the system-specific default keysets in config-
extensions.def. All custom keysets are saved as a whole in config-
extension.cfg. All take effect as soon as one clicks Apply or Ok.
The affected events are '<<force-open-completions>>', '<<expand-word>>',
'<<force-open-calltip>>', '<<flash-paren>>', '<<format-paragraph>>',
'<<run-module>>', '<<check-module>>', and '<<zoom-height>>'. Any
(global) customizations made before 3.6.3 will not affect their keyset-
specific customization after 3.6.3. and vice versa.
Inital patch by Charles Wohlganger, revised by Terry Jan Reedy.
This follows the previous patch that changed idlelib file names.
Class names that matched old module names are not changed.
Change idlelib imports in turtledemo.__main__.
Exception: config-extensions.def. Previously, extension section
names, file names, and class names had to match. Changing section
names would create cross-version conflicts in config-extensions.cfg
(user customizations). Instead map old names to new file names
at point of import in editor.EditorWindow.load_extension.
Patch extensively tested with test_idle, idle_test.htest.py, a custom
import-all test, running IDLE in a console to catch messages,
and testing each menu item. Based on a patch by Al Sweigart.