Add tests for layout overlaying

Add tests to ensure that findViewbyId retrieves the correct view when
an id is overlaid in a RRO.

Also fixes a bug that made strings hardcoded in the overlays.xml
file unable to be retrieved from the string pool.

Bug: 135943783
Test: atest OverlayDeviceTests
Change-Id: I2bf03f151cb696d28f6bb9018eb319af29ba48f4

1 files changed, 6 insertions, 2 deletions

diff --git a/libs/androidfw/Idmap.cpp b/libs/androidfw/Idmap.cpp
index 773353d32d51..6aac4479c3a1 100644
--- a/libs/androidfw/Idmap.cpp
+++ b/libs/androidfw/Idmap.cpp
@@ -53,7 +53,7 @@ OverlayStringPool::~OverlayStringPool() {
 
 const char16_t* OverlayStringPool::stringAt(size_t idx, size_t* outLen) const {
   const size_t offset = dtohl(data_header_->string_pool_index_offset);
-  if (idmap_string_pool_ != nullptr && idx >= size() && idx >= offset) {
+  if (idmap_string_pool_ != nullptr && idx >= ResStringPool::size() && idx >= offset) {
     return idmap_string_pool_->stringAt(idx - offset, outLen);
   }
 
@@ -62,13 +62,17 @@ const char16_t* OverlayStringPool::stringAt(size_t idx, size_t* outLen) const {
 
 const char* OverlayStringPool::string8At(size_t idx, size_t* outLen) const {
   const size_t offset = dtohl(data_header_->string_pool_index_offset);
-  if (idmap_string_pool_ != nullptr && idx >= size() && idx >= offset) {
+  if (idmap_string_pool_ != nullptr && idx >= ResStringPool::size() && idx >= offset) {
     return idmap_string_pool_->string8At(idx - offset, outLen);
   }
 
   return ResStringPool::string8At(idx, outLen);
 }
 
+size_t OverlayStringPool::size() const {
+  return ResStringPool::size() + (idmap_string_pool_ != nullptr ? idmap_string_pool_->size() : 0U);
+}
+
 OverlayDynamicRefTable::OverlayDynamicRefTable(const Idmap_data_header* data_header,
                                                const Idmap_overlay_entry* entries,
                                                uint8_t target_assigned_package_id)