Bug 578413 - improve ConvertLineDelemiter performance

Avoid UI events for every line replaced. Instead construct a replacement
for the whole document content.

Because this is instantaneous there is no progress report within each
file anymore.

+ improve error msg if encoding is wrong to see the affected file upon
multi file convert.

Change-Id: I889e94687815658da46db1592bf2a5b73840b85f
Signed-off-by: Joerg Kubitz <jkubitz-eclipse@gmx.de>
Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.text/+/190155
Tested-by: Platform Bot <platform-bot@eclipse.org>
7 files changed