[BrowserTest]  updates for new bullets/indent UI

DONE: bullets test passes in Firefox and Chrome
DONE: indent/outdent test passes in Firefox and Chrome

TODO: instead of sleep do wait_until for the iframe

Change-Id: Ibcda64dc2457648abf3d5c6bc226b5cc628c0c45
Merge "[BrowserTest]  updates for new bullets/indent UI"