Merge pull request #21792 from davidflanagan/bug1037097

Bug 1037097: restrict image decode size in MediaFrame based on device memory size
Conflicts:
	apps/gallery/manifest.webapp
	apps/sharedtest/test/unit/media_frame_test.js
Merge pull request #21834 from KevinGrandon/bug_1029902_low_memory_features

Bug 1029902 - [Vertical Homescreen] Implement device capability configuration
Merge pull request #21906 from gasolin/issue-1022506

Bug 1022506 - Search results app uses a white icon, rather than a dedica..., r=kgrandon