Fix multi-image TODOs in patchoat.

- Reinstated checks that were still valid (one check was removed).
- Removed unused path that patches only images.

Bug: 26317072

Change-Id: I0e140cb110abbfa469c097c805657ecfdc8552d6
diff --git a/patchoat/patchoat.h b/patchoat/patchoat.h
index cb0d14b..ceddc34 100644
--- a/patchoat/patchoat.h
+++ b/patchoat/patchoat.h
@@ -133,12 +133,11 @@
     if (obj == nullptr) {
       return nullptr;
     }
-    // TODO: Fix these checks for multi-image. Some may still be valid. b/26317072
-    // DCHECK_GT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->Begin()));
-    // DCHECK_LT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->End()));
+    DCHECK_GT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->Begin()));
+    DCHECK_LT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->End()));
     uintptr_t heap_off =
         reinterpret_cast<uintptr_t>(obj) - reinterpret_cast<uintptr_t>(heap_->Begin());
-    // DCHECK_LT(heap_off, image_->Size());
+    DCHECK_LT(heap_off, image_->Size());
     return reinterpret_cast<T*>(image_->Begin() + heap_off);
   }