Don't depend on String8 cast to C string

Bug: 295394788
Test: m checkbuild
Change-Id: I6aa039b6b2a4944e3537ef133f8785890d957edd
diff --git a/media/jni/android_media_MediaCodec.cpp b/media/jni/android_media_MediaCodec.cpp
index 44a0baa..27fc6ae 100644
--- a/media/jni/android_media_MediaCodec.cpp
+++ b/media/jni/android_media_MediaCodec.cpp
@@ -1040,7 +1040,7 @@
     CHECK(ctor != NULL);
 
     ScopedLocalRef<jstring> msgObj(
-            env, env->NewStringUTF(msg != NULL ? msg : String8::format("Error %#x", err)));
+            env, env->NewStringUTF(msg != NULL ? msg : String8::format("Error %#x", err).c_str()));
 
     // translate action code to Java equivalent
     switch (actionCode) {
@@ -2912,7 +2912,7 @@
     if (mode != NATIVE_WINDOW_SCALING_MODE_SCALE_TO_WINDOW
             && mode != NATIVE_WINDOW_SCALING_MODE_SCALE_CROP) {
         jniThrowException(env, "java/lang/IllegalArgumentException",
-                          String8::format("Unrecognized mode: %d", mode));
+                          String8::format("Unrecognized mode: %d", mode).c_str());
         return;
     }
 
@@ -3337,27 +3337,27 @@
     if (err == NAME_NOT_FOUND) {
         // fail and do not try again.
         jniThrowException(env, "java/lang/IllegalArgumentException",
-                String8::format("Failed to initialize %s, error %#x (NAME_NOT_FOUND)", tmp, err));
+                String8::format("Failed to initialize %s, error %#x (NAME_NOT_FOUND)", tmp, err).c_str());
         env->ReleaseStringUTFChars(name, tmp);
         return;
     }
     if (err == NO_MEMORY) {
         throwCodecException(env, err, ACTION_CODE_TRANSIENT,
-                String8::format("Failed to initialize %s, error %#x (NO_MEMORY)", tmp, err));
+                String8::format("Failed to initialize %s, error %#x (NO_MEMORY)", tmp, err).c_str());
         env->ReleaseStringUTFChars(name, tmp);
         return;
     }
     if (err == PERMISSION_DENIED) {
         jniThrowException(env, "java/lang/SecurityException",
                 String8::format("Failed to initialize %s, error %#x (PERMISSION_DENIED)", tmp,
-                err));
+                err).c_str());
         env->ReleaseStringUTFChars(name, tmp);
         return;
     }
     if (err != OK) {
         // believed possible to try again
         jniThrowException(env, "java/io/IOException",
-                String8::format("Failed to find matching codec %s, error %#x (?)", tmp, err));
+                String8::format("Failed to find matching codec %s, error %#x (?)", tmp, err).c_str());
         env->ReleaseStringUTFChars(name, tmp);
         return;
     }