Show more detail in log on brotli errors (eustas)

pagespeed/kernel/util/brotli_inflater.cc

@@ -108,8 +108,12 @@ bool BrotliInflater::DecompressHelper(StringPiece in, MessageHandler* handler,
         // Decompression succeeded, write out the last chunk if needed.
         break;
       case BROTLI_RESULT_ERROR:
-        // TODO(eustas): use brotli API to convert error code to string.
+#ifdef BROTLI_ERROR_CODES_LIST
+        handler->Message(kError, "%s",
+            BrotliErrorString(BrotliGetErrorCode(brotli_state_.get())));
+#else
         handler->Message(kError, "BROTLI_RESULT_ERROR");
+#endif
         return false;
     }
     StringPiece chunk(output, sizeof(output) - available_out);

pagespeed/kernel/util/brotli_inflater_test.cc

@@ -82,7 +82,7 @@ TEST(BrotliInflater, TestCorruptInputBrotliDecompress) {
   StringPiece compressed(kHelloBrotliCorrupt, sizeof(kHelloBrotliCorrupt));
   EXPECT_FALSE(
       BrotliInflater::Decompress(compressed, &handler, &decompress_writer));
-  EXPECT_STREQ("Error: BROTLI_RESULT_ERROR", handler.messages()[0]);
+  EXPECT_TRUE(HasPrefixString(handler.messages()[0], "Error: BROTLI_"));
 }
 
 TEST(BrotliInflater, TestTruncatedInputBrotliDecompress) {