[1/3] Transparent glowpad background

Add transparency to the glowpad view background
so the incoming caller's entire picture can be seen.

[1/3] 透明光圈背景

为来电界面光圈背景添加透明度, 从而让整个
来电用户的照片可见.

[2/3] in platform_frameworks_base
[3/3] in platform_packages_services_Telephony