Support tab UI polish.

Bug: 29107343
Bug: 29101595

1) Changing the font weight of the tabs to Medium
2) Changing the tab indicator color
3) Increasing the padding on the top and bottom of the entire suggestion
space (from 6dp to 8dp)
4) Balancing the space of list components within their perspective list
heights
5) Adjusting the padding on the right side to improve alignment
6) Changing "Suggestions" and suggestions counter font weight and size
7) Removing the drop shadow on the bottom of the suggestion space
8) "More help" subheader has been removed
9) Use 54% #000000 as tint color for more help icons.

Change-Id: If3e1c5ce2701422fba6185e7fa340abccc9bd30c