[historyView] Fix cancel with Modify > Edit and uncommitted changes

When the user pressed "Cancel" on the uncommitted changes dialog, the
history EditHandler would still open the staging and interactive rebase
views.

Bug: 451817
Change-Id: I349e8a05cfaa4926916159ad6861f22807f5da71
Signed-off-by: Robin Stocker <robin@nibor.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Fix missing trailing newline with "Create Patch"

The resulting patches didn't work with "git apply" because the trailing
newline was missing. Adding it makes it work, and it also still works
with Eclipse's "Apply Patch".

Just removing the line with "trim newline" at the end wasn't enough,
because the ByteArrayOutputStream was only overriding one of the write
methods (not the one with just one char). So the last newline was never
added to the StringBuilder. Replace it with a more straightforward
implementation.

Bug: 406134
Change-Id: If736ab3bc5972908a464212a29de8311b32e2718
Signed-off-by: Robin Stocker <robin@nibor.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Fix icon representing commit object in "Push Branch..." wizard

The COMMIT icon is for the action, whereas in the dialog we want the
object. In other places, CHANGESET is used for that.

Change-Id: I6137f60c7c33592b7202e2d84388e749bb63e3ca
Signed-off-by: Robin Stocker <robin@nibor.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>