This change is to update the related UI in the battery page if the
battery is not present. This includes the following updates:
1. Update the summary of battery tile in the Settings homepage
2. Replace the battery level with "Unknown"
3. Replace the summary with help message in the battery page
4. Remove the battery meter icon
Bug: 171368508
Test: verify on an issue device
Change-Id: I892e0d137143160a0bce0c11ce9265120ebb8fd4