Added infinite scrolling to ui:scroller
Add check for valid component when marking value as dirty.

@bug W-1794937@
@rev fabbott@
Merging origin/bob/master-pending/markdirty-valid-cmp into master
[maven-release-plugin] prepare release aura-framework-0.305
[maven-release-plugin] prepare for next development iteration
Merge branch 'release'
Merge branch 'intinite-scrolling' of https://git.soma.salesforce.com/jparadis/aura into jparadis-intinite-scrolling
Merging origin/jay/master-pending-infinite-scrolling into master
[maven-release-plugin] prepare release aura-framework-0.306
[maven-release-plugin] prepare for next development iteration
Merge branch 'release'
Add workaround for nested server dependencies.

@bug W-xxxxxx@

@rev eric.anderson@
Merging origin/goliver/master-pending-cscc-workaround into master
[maven-release-plugin] prepare release aura-framework-0.307
[maven-release-plugin] prepare for next development iteration
Merge branch 'release'
Introduce InvalidComponent prototype switching approach to destroyed
component validation/error handling
Test touch.phone.navigation.PhoneStackPanelUiTest.testClickOnRecentList
is failing

@bug W-1819675@
@rev goliver@
Fixing logging breakage intrdoced when $A.log() was messed with

@rev goliver@
Disable IntegrationServiceImplUITest.testAttributesInitialization in google chrome.

Seems to be hitting a "Maximum call stack size exceeded" problem when running with chromedriver 2.2
@rev gtorres@
@bug W-1819262@