* stable-3.0:
Restore keyboard shortcut for expand all diff context
In plugin list, add placeholders for missing versions
Add Api version to plugin list in PolyGerrit UI
Add Api version to `plugin ls` Ssh command text format
Expose Api version through PluginInfo
When writing temporary plugin files, ensure the directory exists
Update git submodules
Change-Id: Icc9edf9eb93a956f93df0f3fe2d7f48450e5bd30