Provide error message for every single ERR_FAIL, ERR_FAIL_COND etc.

[qarmin]

Issue description:
There is a lot of errors, that shows when using Godot. Some of this errors are not really clear:

core/node_path.cpp:215 - Condition ' !data ' is true. returned: StringName()

ERROR: affine_invert: Condition ' det == 0 ' is true.

At: ./core/cowdata.h:252:resize() - Condition ' psize < 0 ' is true. returned: ERRINVALIDPARAMETER

ERROR: ~List: Condition ' _first != __null ' is true.

Condition ' !id_map.has(p_rid.get_data()) ' is true. returned: __null

editor/plugins/asset_library_editor_plugin.cpp:1206 - Condition 'category_map.has(r["category_id"]) ' is true.

core/class_db.h:186:register_virtual_class() - Condition ' !t ' is true.

So I think, that every ERR_* macro (maybe except ERR_CRASH, ERR_FAIL_INDEX), should provide clear error message.

A lot of ERR_FAIL can be easy to describe, like

godot/core/image.cpp

Line 2058 in 00aabec

ERR_FAIL_COND(p_src.is_null());

ERR_FAIL_COND_MSG(p_src.is_null(), "It isn't valid Image resource.");

godot/core/pool_vector.h

Line 539 in de4aabe

ERR_FAIL_COND_V(alloc->lock > 0, ERR_LOCKED); //can't resize if locked!

ERR_FAIL_COND_V_MSG(alloc->lock > 0, ERR_LOCKED," Can't resize Pool Vector if locked!");

People creating PR should always use ERR_*_MSG because, they should know best what the message should be.

Current number of macros without error message (Godot 3.2 00aabec)

rg "ERR_FAIL[_V]{0,2}\(" | wc -l
228

rg "ERR_FAIL_COND[_V]{0,2}\(" | wc -l
5091

rg "ERR_CONTINUE\(" | wc -l
274

rg "ERR_BREAK\(" | wc -l
50

rg "ERR_FAIL_NULL[_V]{0,2}\(" | wc -l
162

rg "CRASH_COND\(" | wc -l
124

[Calinou]

Closing in favor of #42719, which should hopefully get more discussion going.