Update exploitability rules handle to exclude the root callable name

Summary:
As discussed during program analysis week, this diff removes the root "callable" from the issue handle for exploitability rules.

The handle will now only consist of the exploitability_origin where:
- `explotability_origin.exploitability_root` == the original source to sink flow root method.
- `explotability_origin.callee` == the callee (method or field sink) of the original source to sink flow root method.

Note to self:
- Previous issue with duplicate master issue handles in the *same* root callable: T201904683

Reviewed By: arthaud

Differential Revision: D66032691

fbshipit-source-id: fe102ac7668862c58021f1d739cf62955bb60b31

sapp/pipeline/mariana_trench_parser.py

@@ -225,8 +225,7 @@ def get_master_handle(
         issue_line: int,
     ) -> str:
         return BaseParser.compute_handle_from_key(
-            f"{callable}"
-            f":{issue_callee.to_sapp_handle(callable_line, issue_line)}"
+            f"{issue_callee.to_sapp_handle(callable, callable_line, issue_line)}"
             f":{sink_index}"
             f":{code}"
         )

sapp/pipeline/mariana_trench_parser_objects.py

@@ -461,13 +461,19 @@ def _strip_anonymous_class_numbers(
             f"{stripped_classname}#{relative_line}{callee_signature[first_semicolon:]}"
         )
 
-    def to_sapp_handle(self, callable_line: int, issue_line: int) -> str:
+    def to_sapp_handle(self, callable: str, callable_line: int, issue_line: int) -> str:
         if isinstance(self.callee, ExploitabilityOrigin):
+            # We do not include `callable` in the handle for exploitability issues.
+            # This way, SAPP UI groups all issues with the same exploitability origin
+            # together in the unique issues view.
+            # This does mean that we will write multiple issue instances with the
+            # same issue handle.
             return f"{self.callee.exploitability_root}:{self.callee.callee}"
         elif isinstance(self.callee, str):
-            return IssueCallee._strip_anonymous_class_numbers(
+            callee = IssueCallee._strip_anonymous_class_numbers(
                 self.callee, callable_line, issue_line
             )
+            return f"{callable}:{callee}"
         else:
             raise AssertionError(
                 "Unreachable state for IssueCallee.get_handle() method"