Issue #1333122 by effulgentsia, tim.plunkett: Clarify docs for theme and preprocess/process functions so it is clearer which ones get called for theme functions vs. templates

Issue #1213536 by David_Rothstein, tim.plunkett, sun, effulgentsia, Yorirou, xjm: Fixed Non-resettable theme_get_registry() cache causes problems for non-interactive installations.

Issue #1349722 by kgoel, Everett Zufelt, xjm: Fixed Who's new & Who's online blocks have empty headings.

Issue #1430300 by mradcliffe, xjm, effulgentsia, NROTC_Webmaster: Fixed Preprocess functions in an include file fail to get called when the theme implements a suggestion override.

Issue #1371484 by catch, langworthy, makara, ArtistConk: Fixed Private properties in abstract class DrupalCacheArray.

Issue #1366740 by patrickd: Fixed theme_progress_bar() should have more information about when to use function.

Issue #1322278 by rocket_nova, jhodgdon: Fixed Documentation problem with theme -- doesn't link to theme functions list.

Issue #1011614 by catch, pillarsdotnet: Fixed Theme registry can grow too large for MySQL max_allowed_packet() and memcache default slab size.

Issue #1314396 by rocket_nova: Fixed Documentation for theme_links() should say that Attributes class must be an array .

Issue #1295462 by pillarsdotnet: Fixed Add missing '$' character to docblock for _theme_load_registry() function.

- Patch #952772 by oriol_e9g, mdupont, bleen18, idflood: theme_html_tag() optional value not really optional.

- Patch #774040 by B-Prod, mattyoung: theme_item_list() function duplicates last  value when dealing with children.

Issue #1227426 by Mark Theunissen: Fixed  variable was removed, but is still being assigned in template_preprocess_maintenance_page().

- Patch #1038788 by wojtha, sign: drupal_find_theme_functions() removes all theme 'prefix_' occurences.

Issue #908282 by jbrown, pillarsdotnet: add width and height attributes to increase front-end performance.

Issue #839556 by dalin, jrchamp, effulgentsia, dmitrig01, David_Rothstein: fix isset regression in tablesort, add tests, and cleanup theme_process_registry().

#992376 by larowlan: Fixed Paths containing a hyphen aren't compatible with page theme_hook_suggestions

#599706 follow-up by JohnAlbin, sun: Regression: Restore consistency to theme_menu_local_tasks() theme function

- Patch #647228 by sun, katbailey, Rob Loach: links are needlessly unable to fully participate in D7 AJAX framework features.

- Patch #769226 by Owen Barton, sun, effulgentsia, alanburke, bleen18, mfer: optimize JS/CSS aggregation for front-end performance and DX.

- Patch #561858 by effulgentsia, sun, rfay, Nick_vh, merlinofchaos, katbailey, dereine, tstoeckler: drupal_add_js() and drupal_add_css() to work for AJAX requests too by adding lazy-load to AJAX framework.

- Patch #925490 by David_Rothstein: list_themes() should not call file_exists() on each theme's info file.