[Xposed] Debugger fixes

Debuggers need to know about all methods in a class. For methods hooked with
Xposed, both the hooked (proxy-like) and the original method have to be returned.

Also, the hooked method isn't directly attached to a code item anymore, which
would otherwise be used to calculate offsets into the method code.

Fixes #1.

runtime/debugger.cc

@@ -1605,10 +1605,32 @@ JDWP::JdwpError Dbg::OutputDeclaredMethods(JDWP::RefTypeId class_id, bool with_g
   size_t direct_method_count = c->NumDirectMethods();
   size_t virtual_method_count = c->NumVirtualMethods();
 
-  expandBufAdd4BE(pReply, direct_method_count + virtual_method_count);
+  size_t xposed_method_count = 0;
+  for (size_t i = 0; i < direct_method_count + virtual_method_count; ++i) {
+    mirror::ArtMethod* m = (i < direct_method_count) ? c->GetDirectMethod(i) : c->GetVirtualMethod(i - direct_method_count);
+    if (UNLIKELY(m->IsXposedHookedMethod())) {
+      ++xposed_method_count;
+    }
+  }
+
+  expandBufAdd4BE(pReply, direct_method_count + virtual_method_count + xposed_method_count);
 
   for (size_t i = 0; i < direct_method_count + virtual_method_count; ++i) {
     mirror::ArtMethod* m = (i < direct_method_count) ? c->GetDirectMethod(i) : c->GetVirtualMethod(i - direct_method_count);
+
+    if (UNLIKELY(xposed_method_count > 0 && m->IsXposedHookedMethod())) {
+      expandBufAddMethodId(pReply, ToMethodId(m));
+      expandBufAddUtf8String(pReply, m->GetName());
+      expandBufAddUtf8String(pReply, m->GetSignature().ToString());
+      if (with_generic) {
+        static const char genericSignature[1] = "";
+        expandBufAddUtf8String(pReply, genericSignature);
+      }
+      expandBufAdd4BE(pReply, MangleAccessFlags(m->GetAccessFlags()));
+
+      m = m->GetXposedOriginalMethod();
+    }
+
     expandBufAddMethodId(pReply, ToMethodId(m));
     expandBufAddUtf8String(pReply, m->GetName());
     expandBufAddUtf8String(pReply, m->GetSignature().ToString());

runtime/mirror/art_method-inl.h

@@ -467,6 +467,9 @@ inline const char* ArtMethod::GetName() {
 }
 
 inline const DexFile::CodeItem* ArtMethod::GetCodeItem() {
+  if (UNLIKELY(IsXposedHookedMethod())) {
+    return nullptr;
+  }
   mirror::ArtMethod* method = GetInterfaceMethodIfProxy();
   return method->GetDexFile()->GetCodeItem(method->GetCodeItemOffset());
 }