ConnectivityService: minor formatting change

This patch adds a space character between "synchronized" and
"(mTheLockVariable)" so that all synchronized block have a consistent
syntax. Basic stats shows that "synchronized (" is x10 time more likely
than "synchronized(".

This facilitates finding all locked sections by grepping.

Test: no semantics changes
Bug: 37119619
Change-Id: Id860700efa85ffebafed11af3a2997bc115d9c03