goog.ui.TweakUi
The goog.tweak package provides a convenient and flexible way to add
configurable settings to an app. These settings:
  - can be set at compile time
  
- can be set in code (using goog.tweak.overrideDefaultValue)
  
- can be set by query parameters
  
- can be set through the TweakUi interface
Tweaks IDs are checked by the compiler and tweaks can be fully removed when
tweakProcessing=STRIP. Tweaks are great for toggling debugging facilities.A collapsible menu
An expanded menu
  - When "Apply Tweaks" is clicked, all non-default values are encoded into
  query parameters and the page is refreshed.
  
- Blue entries are ones where the value of the tweak will change without
  clicking apply tweaks (the value of goog.tweak.get*() will change)