* Large cleanup in _FindLineBreak(), be a bit more clever by storing the found
offsets instead of calculating them multiple times, use
_TabExpandedStyledWidth() instead of _StyledWidth() and manual tab calculation
which was also broken (it assumed tabs were consequtive which was possibly not
the case).
* Modified CanEndLine() to also return true when going from non-whitespace to
whitespace and the other way around which is more logical (so we'd break after
the word and not after word + whitespace, even though we actually do that
in the end by eating whitespace after words in _FindLineBreak()).
* The TextGapBuffer is not necessarily 0 terminated, so RealCharAt() needs to
check if the index is at the end of the string and return 0 in that case.
Before it would access the buffer "out by one" which could've lead to a crash.
* Simplified the gap moving calculations by removing some no-op calculations.
* Added debugger calls in TextGapBuffer in case of invalid use.
* Some minor cleanup.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36304 a95241bf-73f2-0310-859d-f6bbb57e9c96
Michael Lotz
5c4e7641a7