Add a separate error and diagnostic group to allow configuring the @struct/@dict inheritence warnings.  This allows the @struct inheritence warnings to be turned off for projects using a legacy code as base classes but still deriving some benefit from better checks on inpropriate property additions.

R=blickly
DELTA=13 (10 added, 0 deleted, 3 changed)


Revision created by MOE tool push_codebase.
MOE_MIGRATION=6257


git-svn-id: http://closure-compiler.googlecode.com/svn/trunk@2506 b0f006be-c8cd-11de-a2e8-8d36a3108c74
Add new error string implemented by w3c speech recognition api.

R=nicksantos
DELTA=2 (2 added, 0 deleted, 0 changed)


Revision created by MOE tool push_codebase.
MOE_MIGRATION=6258


git-svn-id: http://closure-compiler.googlecode.com/svn/trunk@2507 b0f006be-c8cd-11de-a2e8-8d36a3108c74