Except few cases simple type inferring, one place required a more
complex refactoring.

JMM maintained (for some obscure reasons) a temporary entry in the
PerProjectInfo.secondaryTypes map (with the key INDEXED_SECONDARY_TYPES)
containing ... another map with different type bounds, being used during
search. Instead of maintaining an incompatible entry within the
PerProjectInfo.secondaryTypes map we replace here it with a new field
PerProjectInfo.indexingSecondaryCache.

Change-Id: Ie7cc7a9e64e03624c8fad464208ebcdd86800000
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>