Don't treat SPACE as the start of a keyboard search.
Add KeyNavContainer robot test.
Fixes #17766.
Fix menu positioning when opened via keyboard.  Fixes #17769.

Changes include:
  - make keydown handler process context-menu key in addition to shift-F10
  - (for keyboard) open menu around focused node rather than node matching
    this.targetNodeIds / this.selector
  - different approach to avoid repeat contextmenu key event;
    1ms delay in _scheduleOpen() was too short; there's about 100ms between
    the keydown and contextmenu events on IE8
remove unneeded CSS that flummoxes IE, fixes #17672
fix tooltips on SVG nodes on FF, fixes #16310
fixes #17751 use native placeholder support for form inputs
reuse background iframes between (non-currently shown) popups, fixes #17774
Added unit test assertion for #17746
fix dijit typos, refs #17778
Prevent container scrolling in IE on long tree labels

Fixes #17765.
Revert "fixes #17751 use native placeholder support for form inputs"

This reverts commit 63486c0569d7ba60e351cf01f36dd8f007ed3b48.

This commit caused backwards-incompatible changes to the toolkit
that will break existing users, and introduces a feature that
is not cross-browser compatible (HTML5 placeholder styling is
not consistent) in order to fix an unrelated defect.
fix #16482 Regression: _WidgetBase#placeAt() can't be used on a
DocumentFragment

* added tests for placement using document fragment
* updated WidgetBase.placeAt to allow a document fragment
Limit background iframe to IE; it's no longer needed on other browsers.
Also switch test from java applet to PDF, since the java applet wasn't loading correctly.
Fixes #17811, refs #11822.
Avoid double destroy when handle has multiple destroy methods
(ex: destroy() and cancel()).  Fixes #17763.

Thanks Benjamin Santalucia for patch!
avoid more webkit spurious warnings, fixes #17824
Fix TextBox.on("keypress", ...), fixes #17826, refs #17154.
Also adds test case for #17154 (TextBox in Toolbar).
hardcode test locale to en-us to avoid spurious failures, fixes #17818
skip robot tests on iOS and android, refs #17819, #17820
avoid timeout on CheckBoxMixin test, refs #17819, #17820
Convert most remaining AMD test files to use boilerplate.js.
Boilerplate.js sets the locale to en-us, avoiding spurious test
failures on non-US locales.

Refs #17818.
hardcode test locale to en-us to avoid spurious failure, refs #17818