If line gets successfully retrieved from subrange instead of
primaryrange get file index from the subrange since the line might be
from a different file for inlined methods.

When using -H:+OmitInlinedMethodDebugLineInfo we know that ranges are
not expected to have inlined subranges so we can avoid looping over
them to see if we need to generate inline debug info.

…tions

This way we save space and time by not replicating abstract inline DIEs
in the caller's CU.

* remove line records with zero extent
* remove caller marking substitution entry (bci = -1)

…eInfo

PrimaryEntry provides a top-down subrange iterator that performs a
depth-first traversal of the call-graph and a leaf subrange iterator
that performs a depth-first traversal returning only the leafs.

The sibling nodes in the tree are being merged whenever possible to
reduce the debuginfo size.

Co-authored-by: Foivos Zakkak <fzakkak@redhat.com>

Co-authored-by: Andrew Dinn <adinn@redhat.com>

This way we avoid the expensive calls to "toJavaName".

This patch reduces the time spend in debug info generation from ~12s to
5s.