Adding convenience method for common accessor to required element on component.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47565620
Update timer usage in xhrio.  We have seen occasional early timer-firing in IE9 test
VMs.  This CL changes XhrIo to use HTML5 XMLHttpRequest Level 2 'timeout' and 'ontimeout' when they are available.  Currently, they are found and supported in IE9 and IE10.  They are present, but were found not to work in FireFox.  They are not supported in Chrome.

For FF and Chrome, this CL updates the code to use goog.Timer rather than calling setTimeout() directly.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47571197
Automated rollback

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47580754
Templatize goog.date.min and goog.date.max to be able to use their return values without casting.
On the downside the type checking of the arguments is lost.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47583771
Assert that the template being rendered can legally be a child of a
div, to warn developers if they try to render e.g a <tr> as an element
or fragment.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47604123
Correct issues
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47607082
Reinstate CL
This CL adds whitelisting to determine when to use the XHR2 'timeout' support.
Field detection turned out to be too fallible.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47619824
Add functions that can protect entry points for
window.requestAnimationFrame and goog.async.nextTick.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47627579
Makes the delay added for WebDriver configurable by tests.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47655598
Remove the correct set of modules from the requested modules when
retrying and both concurrent and batch mode are enabled.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47656844
Add a function to optionally allow numbers to be formatted based on the formatting of a different number. This is only for compact decimal formatting. It will allow 1,000,000 to be formatted as '1,000K' instead of '1M', which is useful when the same formatting is desired for a set of numbers such as on the axis of a chart.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47683275
Create a local version of WebChannel implementation as WebChannelBase, with goog.net.browserchannel as the baseline (for tracking changes).

Extensive cleanup and refactoring will follow right after this CL, before we merge existing browserchannel2 (protocol) changes.

WebChannelRequestStats and WebChannelRequestSupport are introduced to break circular dependency between the channel and request class.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47684994
Updates onDocumentBlur_ inside goog.ui.PopupBase since all major browsers now support document.activeElement.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47795762
Remove require of "goog.useragent", which doesn't exist, and is
unused.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47806919
Fix DatePicker.decorateInternal_ so that it preserves existing classes of the decorated element.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=47866056