[debugger] add lcov support to d8.

src/d8.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_D8_H_
 #define V8_D8_H_
 
 #include <iterator>
 #include <memory>
 #include <string>
@@ skipping 286 matching lines @@
         expected_to_throw(false),
         mock_arraybuffer_allocator(false),
         enable_inspector(false),
         num_isolates(1),
         compile_options(v8::ScriptCompiler::kNoCompileOptions),
         isolate_sources(NULL),
         icu_data_file(NULL),
         natives_blob(NULL),
         snapshot_blob(NULL),
         trace_enabled(false),
-        trace_config(NULL) {}
+        trace_config(NULL),
+        lcov_file(NULL) {}
 
   ~ShellOptions() {
     delete[] isolate_sources;
   }
 
   bool use_interactive_shell() {
     return (interactive_shell || !script_executed) && !test_shell;
   }
 
   bool script_executed;
@@ skipping 10 matching lines @@
   bool mock_arraybuffer_allocator;
   bool enable_inspector;
   int num_isolates;
   v8::ScriptCompiler::CompileOptions compile_options;
   SourceGroup* isolate_sources;
   const char* icu_data_file;
   const char* natives_blob;
   const char* snapshot_blob;
   bool trace_enabled;
   const char* trace_config;
+  const char* lcov_file;
 };
 
 class Shell : public i::AllStatic {
  public:
   static MaybeLocal<Script> CompileString(
       Isolate* isolate, Local<String> source, Local<Value> name,
       v8::ScriptCompiler::CompileOptions compile_options);
   static bool ExecuteString(Isolate* isolate, Local<String> source,
                             Local<Value> name, bool print_result,
                             bool report_exceptions);
@@ skipping 109 matching lines @@
   static base::OS::MemoryMappedFile* counters_file_;
   static base::LazyMutex context_mutex_;
   static const base::TimeTicks kInitialTicks;
 
   static base::LazyMutex workers_mutex_;
   static bool allow_new_workers_;
   static i::List<Worker*> workers_;
   static std::vector<ExternalizedContents> externalized_contents_;
 
   static void WriteIgnitionDispatchCountersFile(v8::Isolate* isolate);
+  // Append LCOV coverage data to file.
+  static void WriteLcovData(v8::Isolate* isolate, const char* file);
   static Counter* GetCounter(const char* name, bool is_histogram);
   static Local<String> Stringify(Isolate* isolate, Local<Value> value);
   static void Initialize(Isolate* isolate);
   static void RunShell(Isolate* isolate);
   static bool SetOptions(int argc, char* argv[]);
   static Local<ObjectTemplate> CreateGlobalTemplate(Isolate* isolate);
   static MaybeLocal<Context> CreateRealm(
       const v8::FunctionCallbackInfo<v8::Value>& args);
   static MaybeLocal<Module> FetchModuleTree(v8::Local<v8::Context> context,
                                             const std::string& file_name);
 };
 
 
 }  // namespace v8
 
 
 #endif  // V8_D8_H_