add some methods for browser

Change-Id: I4e8e7542d35fdd896a5d6f3de2e85b15a056d7fd
not destroy miui home when "always-finish" switch on

N/A

Change-Id: I24f517f752c3be003cdc68732415f2bb4ad48320
Ref-Id: Iaeda8ec06d76b019fba6f2d58617943af7ca1d75
pick code from android 4.2, fix media scanner slow issue

MIUI-14439

Change-Id: Iebc81be6aebb57c8cce6b00ec9bb3b51441578db
Ref-Id: I67a008073070dfb48c3fb5d3a522dfd00a5c3a3c
add public method hideFloatView for browser

Change-Id: Idb93406b6f4f3019dab62f5f39666d70f7ce2ccc
update android src of [jellybean]

Change-Id: Ica2da3adac66e4c5d8ca41aa19d809a5f2f2322b
update android src of [jellybean]

Change-Id: I5ba268f3cc20f80cb8ac6321e867c2718d658f1d
update android src of [jellybean]

Change-Id: I6b586053e39cedb0c0522abe71e6fb02784f75eb
update android src of [jellybean]

Change-Id: I3d5363847dffcd2cf8bc4069f4b69a0c1e2dbebb
update android src of [jellybean]

Change-Id: I562bb35c166777d60cd3506ab383566ac749c4aa
update android src of [jellybean]

Change-Id: I4296cdf4a867d0953a1e60600040098e75f572a3
update android src of [jellybean]

Change-Id: I221a7a7ae7cf392812bd877e907a8c2cbb402723
update android src of [jellybean]

Change-Id: Ie517641568f136236962260d6617180e1b558ff3
update android src of [jellybean]

Change-Id: Id88723dee38c465e88ebc9de891b049018450a52
update android src of [jellybean]

Change-Id: I6cf8ada6c17d13919f4878e683b18902023a4bc9