Support contextual-biasing for streaming model (#184)

* Support contextual-biasing for streaming model

* The whole pipeline runs normally

* Fix comments

sherpa-onnx/csrc/online-recognizer.h

@@ -75,7 +75,10 @@ struct OnlineRecognizerConfig {
   std::string decoding_method = "greedy_search";
   // now support modified_beam_search and greedy_search
 
-  int32_t max_active_paths = 4;  // used only for modified_beam_search
+  // used only for modified_beam_search
+  int32_t max_active_paths = 4;
+  /// used only for modified_beam_search
+  float context_score = 1.5;
 
   OnlineRecognizerConfig() = default;
 
@@ -85,13 +88,14 @@ struct OnlineRecognizerConfig {
                          const EndpointConfig &endpoint_config,
                          bool enable_endpoint,
                          const std::string &decoding_method,
-                         int32_t max_active_paths)
+                         int32_t max_active_paths, float context_score)
       : feat_config(feat_config),
         model_config(model_config),
         endpoint_config(endpoint_config),
         enable_endpoint(enable_endpoint),
         decoding_method(decoding_method),
-        max_active_paths(max_active_paths) {}
+        max_active_paths(max_active_paths),
+        context_score(context_score) {}
 
   void Register(ParseOptions *po);
   bool Validate() const;
@@ -112,6 +116,10 @@ class OnlineRecognizer {
   /// Create a stream for decoding.
   std::unique_ptr<OnlineStream> CreateStream() const;
 
+  // Create a stream with context phrases
+  std::unique_ptr<OnlineStream> CreateStream(
+      const std::vector<std::vector<int32_t>> &context_list) const;
+
   /**
    * Return true if the given stream has enough frames for decoding.
    * Return false otherwise