Ensure to use api.<category>.<method>

In the current code both api.<method> and api.<category>.<method> are used.
Using api.<method> directly makes it difficult to identify which module
defined a method and forces developers to use unique method names among
projects. This commit removes api.<method> style method calls.

Change-Id: Iaefa1061f99b7865e02541df87c112a6b2868ec0
Merge "Ensure to use api.<category>.<method>"