Use String8/16 c_str [idmap2, androidfw]

Bug: 295394788
Test: make checkbuild
Change-Id: I95264e8bfc96a5adb7f7cc55a24dc0e8c126371d
diff --git a/libs/androidfw/tests/ConfigDescription_test.cpp b/libs/androidfw/tests/ConfigDescription_test.cpp
index ec478b0..07bd175 100644
--- a/libs/androidfw/tests/ConfigDescription_test.cpp
+++ b/libs/androidfw/tests/ConfigDescription_test.cpp
@@ -159,17 +159,17 @@
   EXPECT_TRUE(TestParse("feminine", &config));
   EXPECT_EQ(android::ResTable_config::GRAMMATICAL_GENDER_FEMININE, config.grammaticalInflection);
   EXPECT_EQ(SDK_U, config.sdkVersion);
-  EXPECT_EQ(std::string("feminine-v34"), config.toString().string());
+  EXPECT_EQ(std::string("feminine-v34"), config.toString().c_str());
 
   EXPECT_TRUE(TestParse("masculine", &config));
   EXPECT_EQ(android::ResTable_config::GRAMMATICAL_GENDER_MASCULINE, config.grammaticalInflection);
   EXPECT_EQ(SDK_U, config.sdkVersion);
-  EXPECT_EQ(std::string("masculine-v34"), config.toString().string());
+  EXPECT_EQ(std::string("masculine-v34"), config.toString().c_str());
 
   EXPECT_TRUE(TestParse("neuter", &config));
   EXPECT_EQ(android::ResTable_config::GRAMMATICAL_GENDER_NEUTER, config.grammaticalInflection);
   EXPECT_EQ(SDK_U, config.sdkVersion);
-  EXPECT_EQ(std::string("neuter-v34"), config.toString().string());
+  EXPECT_EQ(std::string("neuter-v34"), config.toString().c_str());
 }
 
 }  // namespace android