[polymer] Fix bug where the process memory dump tab was unselectable
[polymer] Fix bug where the process memory dump tab was unselectable

This would happen whenever a "global memory dump" tab was also present.
This is because the selection worked based on the ID of the tab being
selected, which was in turn based on the name of the sub view tag name.
Because global memory dump and process memory dump use the same
Polymer element, and thus used the same ID, selecting either would
always select the global memory dump tab.

NOPRESUBMIT=true
NOTRY=true
BUG=catapult:#2477

Review-Url: https://codereview.chromium.org/2153563002

benschmaus/catapult,sahiljain/catapult,sahiljain/catapult,catapult-project/catapult,sahiljain/catapult,catapult-project/catapult-csm,catapult-project/catapult,catapult-project/catapult-csm,sahiljain/catapult,sahiljain/catapult,benschmaus/catapult,benschmaus/catapult,catapult-project/catapult,catapult-project/catapult-csm,catapult-project/catapult,catapult-project/catapult-csm,catapult-project/catapult-csm,benschmaus/catapult,catapult-project/catapult-csm,catapult-project/catapult,catapult-project/catapult-csm,benschmaus/catapult,benschmaus/catapult,benschmaus/catapult,catapult-project/catapult,sahiljain/catapult,catapult-project/catapult