Fix buildbots hidden_api_test

Target buildbots set /system to be the runtime module root because they
are running without an apex. The test assumes that /system dex files are assigned
to the application domain but here they get assigned to the core-platform domain.

Adjust the domain setting logic to check if the runtime module root is
distict from the android root (as a proxy for 'is running with apex').
If not (as is the case with the buildbots), skip checks against apex
locations.

Test: m test-art-target-gtest-hidden_api_test
Change-Id: Iff3890ec69cb04a1e4ed5bc2a3b5c652ada05f36
diff --git a/runtime/hidden_api_test.cc b/runtime/hidden_api_test.cc
index be64079..70fafe6 100644
--- a/runtime/hidden_api_test.cc
+++ b/runtime/hidden_api_test.cc
@@ -17,6 +17,7 @@
 #include "hidden_api.h"
 
 #include <fstream>
+#include <sstream>
 
 #include "base/file_utils.h"
 #include "base/sdk_version.h"
@@ -431,20 +432,25 @@
 
 static bool CheckAllDexFilesInDomain(ObjPtr<mirror::ClassLoader> loader,
                                      const std::vector<std::unique_ptr<const DexFile>>& dex_files,
-                                     hiddenapi::Domain expected_domain)
+                                     hiddenapi::Domain expected_domain,
+                                     /* out */ std::string* error_msg)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   for (const auto& dex_file : dex_files) {
     hiddenapi::AccessContext context(loader, dex_file.get());
     if (context.GetDomain() != expected_domain) {
-      LOG(ERROR) << dex_file->GetLocation() << ": access context domain does not match "
+      std::stringstream ss;
+      ss << dex_file->GetLocation() << ": access context domain does not match "
           << "(expected=" << static_cast<uint32_t>(expected_domain)
           << ", actual=" << static_cast<uint32_t>(context.GetDomain()) << ")";
+      *error_msg = ss.str();
       return false;
     }
     if (dex_file->GetHiddenapiDomain() != expected_domain) {
-      LOG(ERROR) << dex_file->GetLocation() << ": dex file domain does not match "
+      std::stringstream ss;
+      ss << dex_file->GetLocation() << ": dex file domain does not match "
           << "(expected=" << static_cast<uint32_t>(expected_domain)
           << ", actual=" << static_cast<uint32_t>(dex_file->GetHiddenapiDomain()) << ")";
+      *error_msg = ss.str();
       return false;
     }
   }
@@ -466,7 +472,10 @@
   ASSERT_TRUE(LoadDexFiles(data_location_path, soa, &dex_files, &class_loader, &error_msg))
       << error_msg;
   ASSERT_GE(dex_files.size(), 1u);
-  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader, dex_files, hiddenapi::Domain::kApplication));
+  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader,
+                                       dex_files,
+                                       hiddenapi::Domain::kApplication,
+                                       &error_msg)) << error_msg;
 
   dex_files.clear();
   ASSERT_EQ(0, remove(data_location_path.c_str()));
@@ -486,7 +495,10 @@
   ASSERT_TRUE(LoadDexFiles(system_location_path, soa, &dex_files, &class_loader, &error_msg))
       << error_msg;
   ASSERT_GE(dex_files.size(), 1u);
-  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader, dex_files, hiddenapi::Domain::kApplication));
+  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader,
+                                       dex_files,
+                                       hiddenapi::Domain::kApplication,
+                                       &error_msg)) << error_msg;
 
   dex_files.clear();
   ASSERT_EQ(0, remove(system_location_path.c_str()));
@@ -510,7 +522,10 @@
                            &class_loader,
                            &error_msg)) << error_msg;
   ASSERT_GE(dex_files.size(), 1u);
-  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader, dex_files, hiddenapi::Domain::kPlatform));
+  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader,
+                                       dex_files,
+                                       hiddenapi::Domain::kPlatform,
+                                       &error_msg)) << error_msg;
 
   dex_files.clear();
   ASSERT_EQ(0, remove(system_framework_location_path.c_str()));
@@ -531,7 +546,10 @@
   ASSERT_TRUE(LoadDexFiles(data_multi_location_path, soa, &dex_files, &class_loader, &error_msg))
       << error_msg;
   ASSERT_GE(dex_files.size(), 1u);
-  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader, dex_files, hiddenapi::Domain::kApplication));
+  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader,
+                                       dex_files,
+                                       hiddenapi::Domain::kApplication,
+                                       &error_msg)) << error_msg;
 
   dex_files.clear();
   ASSERT_EQ(0, remove(data_multi_location_path.c_str()));
@@ -553,7 +571,10 @@
   ASSERT_TRUE(LoadDexFiles(system_multi_location_path, soa, &dex_files, &class_loader, &error_msg))
       << error_msg;
   ASSERT_GT(dex_files.size(), 1u);
-  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader, dex_files, hiddenapi::Domain::kApplication));
+  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader,
+                                       dex_files,
+                                       hiddenapi::Domain::kApplication,
+                                       &error_msg)) << error_msg;
 
   dex_files.clear();
   ASSERT_EQ(0, remove(system_multi_location_path.c_str()));
@@ -579,7 +600,10 @@
                            &class_loader,
                            &error_msg)) << error_msg;
   ASSERT_GT(dex_files.size(), 1u);
-  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader, dex_files, hiddenapi::Domain::kPlatform));
+  ASSERT_TRUE(CheckAllDexFilesInDomain(class_loader,
+                                       dex_files,
+                                       hiddenapi::Domain::kPlatform,
+                                       &error_msg)) << error_msg;
 
   dex_files.clear();
   ASSERT_EQ(0, remove(system_framework_multi_location_path.c_str()));