[lldb] Introduce internal stop hooks (#164506)

Introduce the concept of internal stop hooks.
These are similar to LLDB's internal breakpoints:
LLDB itself will add them and users of LLDB will
not be able to add or remove them.

This change adds the following 3
independently-useful concepts:
* Maintain a list of internal stop hooks that will be populated by LLDB
and cannot be added to or removed from by users. They are managed in a
separate list in `Target::m_internal_stop_hooks`.
* `StopHookKind:CodeBased` and `StopHookCoded` represent a stop hook
defined by a C++ code callback (instead of command line expressions or a
Python class).
* Stop hooks that do not print any output can now also suppress the
printing of their header and description when they are hit via
`StopHook::GetSuppressOutput`.

Combining these 3 concepts we can model "internal
stop hooks" which serve the same function as
LLDB's internal breakpoints: executing built-in,
LLDB-defined behavior, leveraging the existing
mechanism of stop hooks.

This change also simplifies
`Target::RunStopHooks`.  We already have to
materialize a new list for combining internal and
user stop hooks. Filter and only add active hooks to this list to avoid
the need for "isActive?"
checks later on.

1 files changed, 1 insertions, 3 deletions

diff --git a/lldb/source/Commands/CommandObjectBreakpoint.cpp b/lldb/source/Commands/CommandObjectBreakpoint.cpp
index de0a7e7..5a55126 100644
--- a/lldb/source/Commands/CommandObjectBreakpoint.cpp
+++ b/lldb/source/Commands/CommandObjectBreakpoint.cpp
@@ -1114,9 +1114,7 @@ public:
   CommandObjectBreakpointList(CommandInterpreter &interpreter)
       : CommandObjectParsed(
             interpreter, "breakpoint list",
-            "List some or all breakpoints at configurable levels of detail.",
-            nullptr) {
-    CommandArgumentData bp_id_arg;
+            "List some or all breakpoints at configurable levels of detail.") {
 
     // Define the first (and only) variant of this arg.
     AddSimpleArgumentList(eArgTypeBreakpointID, eArgRepeatOptional);