Be sure we to read all bytes requested, in GetRandomBytes.

runtime/bin/crypto_android.cc

Index: runtime/bin/crypto_android.cc
diff --git a/runtime/bin/crypto_android.cc b/runtime/bin/crypto_android.cc
index 8922a5e4c1942891c6addc8ad2065b2897ef2754..9a81ed17e9ff25f9d9c9fbf4fba2ac3100a29e3c 100644
--- a/runtime/bin/crypto_android.cc
+++ b/runtime/bin/crypto_android.cc
@@ -20,8 +20,8 @@ namespace bin {
 bool Crypto::GetRandomBytes(intptr_t count, uint8_t* buffer) {
   intptr_t fd = TEMP_FAILURE_RETRY(open("/dev/urandom", O_RDONLY));
   if (fd < 0) return false;
-  intptr_t bytes_read = read(fd, buffer, count);
-  close(fd);
+  intptr_t bytes_read = FDUtils::ReadFromBlocking(fd, buffer, count);
+  VOID_TEMP_FAILURE_RETRY(close(fd));
   return bytes_read == count;
 }