Update stringly-typed method refs to account for colon

Summary:
We added a colon to the method descriptor string used by ProguardMap
and the canonical-name form of DexMethod::get_method.  This is why using strings
to represent complex data is bad.

This was causing remove-unreachable to go haywire, since it's driven by seeds
information, which is in turn parsed using these assumptions.

Reviewed By: satnam6502

Differential Revision: D4000864

fbshipit-source-id: 561b67794f518d534cce16dab6ee9580bfb44ff6

libredex/DexClass.cpp

@@ -447,8 +447,8 @@ std::vector<std::string> split_args(std::string args) {
 DexMethod* DexMethod::get_method(std::string canon) {
   auto cls_end = canon.find('.');
   auto name_start = cls_end + 1;
-  auto name_end = canon.find('(', name_start);
-  auto args_start = name_end + 1;
+  auto name_end = canon.find(':', name_start);
+  auto args_start = name_end + 2;
   auto args_end = canon.find(')', args_start);
   auto rtype_start = args_end + 1;
   auto cls_str = canon.substr(0, cls_end);

libredex/ReachableClasses.cpp

@@ -533,7 +533,7 @@ struct SeedsParser {
     return
       convert_type(cls)
       + "." + name
-      + "(" + convert_args(args) + ")"
+      + ":(" + convert_args(args) + ")"
       + convert_type(type);
   }