Remove Incoming Call Background / Add Flip to Mute/Reject

Revert "InCallUI: add Incoming Call Background (non-Intrusive InCall improvement)"

This reverts commit 82765f87d3ac8d5662383ff35c0143ede7f44629.

Change-Id: Ia2ebebb102fc4b55983d1e7f7fd30f426c6f8ac7

InCallUI: Disable Back button on Non-intursive InCall Card

Fix for jira issue http://jira.omnirom.org/browse/OMNI-296

PS2 to PS5: code cleanup

PS6: Remove Jira issue url from code

Change-Id: I257daccbb175265e2430f1b0b30c9175cb4b1981

[3/3] InCallUI: Flip to Mute/Reject Call

Actual Logic for this functionality.

PS2: Remove unwanted space

Base: https://gerrit.omnirom.org/#/c/4668/
Telephony: https://gerrit.omnirom.org/#/c/4670/

Change-Id: Ia10df0045e9919c6b7efc97857abaeba246c365d

InCallUI: Flip to Mute/Reject Call cleanup: fix ITelephony access

Using reflection to access ITelephony is a strange idea

Change-Id: Ia34b135460cc2b85fbd5db4585228a015c2a52b1

[1/2] InCallUI: unify flip action handler

We cannot share the code since DeskClock is only using
the app API but we can at least share the file

PS2
NPE derp

Change-Id: I1c5bfc36c18d00f91dcb5d2dcfe646543efdb205