Merge pull request #12448 from comoyo/render_speed

Bug 875963 - Switch case without rebuilding keyboard. r=RudyL(cherry picked from commit 74f49f0a1ba192056a4e529d3b1290144374011a)

Conflicts:
	apps/keyboard/js/render.js
Merge pull request #15309 from comoyo/bug959175

Bug 959175 - Force redraw on uppercase switch when layout has secondLayout flag. r=RudyL(cherry picked from commit e553ba3a0cdf9b4bfaa4d946279e31a0eacb2806)

Conflicts:
	apps/keyboard/js/render.js
Merge pull request #17019 from RudyLu/Bug875963_uplift_1.3T

Uplift Bug 875963 and Bug 959175 to 1.3t
a=1.3T+