Remove most of the `===DONE===` tags and its variations.
Keep `===DONE===` if the test output otherwise becomes empty.

Closes GH-4872.

RFC: https://wiki.php.net/rfc/typed_properties_v2

This is a squash of PR #3734, which is a squash of PR #3313.

Co-authored-by: Bob Weinand <bobwei9@hotmail.com>
Co-authored-by: Joe Watkins <krakjoe@php.net>
Co-authored-by: Dmitry Stogov <dmitry@zend.com>

This patch adds missing newlines, trims multiple redundant final
newlines into a single one, and trims redundant leading newlines in all
*.phpt sections.

According to POSIX, a line is a sequence of zero or more non-' <newline>'
characters plus a terminating '<newline>' character. [1] Files should
normally have at least one final newline character.

C89 [2] and later standards [3] mention a final newline:
"A source file that is not empty shall end in a new-line character,
which shall not be immediately preceded by a backslash character."

Although it is not mandatory for all files to have a final newline
fixed, a more consistent and homogeneous approach brings less of commit
differences issues and a better development experience in certain text
editors and IDEs.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_206
[2] https://port70.net/~nsz/c/c89/c89-draft.html#2.1.1.2
[3] https://port70.net/~nsz/c/c99/n1256.html#5.1.1.2

This implements a reduced variant of #1226 with just the following
change:

-Fatal error: Uncaught exception 'EngineException' with message 'Call to private method foo::bar() from context ''' in %s:%d
+Fatal error: Uncaught EngineException: Call to private method foo::bar() from context '' in %s:%d

The '' wrapper around messages is very weird if the exception
message itself contains ''. Futhermore having the message wrapped
in '' doesn't work for the "and defined" suffix of
TypeExceptions.

TypeException stays as-is for now because it uses messages that are
incompatible with the way exception messages are displayed.

closure_038.phpt and a few others now show that we're generating
too many exceptions for compound operations on undefined properties
-- this needs to be fixed in a followup.

The fix breaks two SimpleXML tests those must be fixed