Fixed assert in flatc converting to text.

Change-Id: Idac375b22aa9beaba162084cc3396f5536a4e721
Tested: on Linux.

include/flatbuffers/flatbuffers.h

@@ -582,6 +582,11 @@ class FlatBufferBuilder FLATBUFFERS_FINAL_CLASS {
     buf_.fill(PaddingBytes(buf_.size(), elem_size));
   }
 
+  void PushFlatBuffer(const uint8_t *bytes, size_t size) {
+    PushBytes(bytes, size);
+    finished = true;
+  }
+
   void PushBytes(const uint8_t *bytes, size_t size) {
     buf_.push(bytes, size);
   }

src/flatc.cpp

@@ -201,13 +201,13 @@ int main(int argc, const char *argv[]) {
           ++file_it) {
       std::string contents;
       if (!flatbuffers::LoadFile(file_it->c_str(), true, &contents))
-        Error("unable to load file" + *file_it);
+        Error("unable to load file: " + *file_it);
 
       bool is_binary = static_cast<size_t>(file_it - filenames.begin()) >=
                        binary_files_from;
       if (is_binary) {
         parser.builder_.Clear();
-        parser.builder_.PushBytes(
+        parser.builder_.PushFlatBuffer(
           reinterpret_cast<const uint8_t *>(contents.c_str()),
           contents.length());
         if (!raw_binary) {