Simplify profiler output class selection

Simplify profiler output class selection

Instead of maintaining a mapping of short names to class names ('db' =>
'ProfilerOutputDb', etc.), let us adopt the convention of using the full
class name to indicate the output type. We can maintain backward-compatibility
by using simple string manipulation to transform short names to the full class
names.

Change-Id: I976e0da2873d88b9892fb41823cfe3af0a2d3974