[debug] introduce precise binary code coverage.

src/d8.cc

 // 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.
 
 #include <errno.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
 
 #include <algorithm>
@@ skipping 1674 matching lines @@
   std::ofstream dispatch_counters_stream(
       i::FLAG_trace_ignition_dispatches_output_file);
   dispatch_counters_stream << *String::Utf8Value(
       JSON::Stringify(context, dispatch_counters).ToLocalChecked());
 }
 
 // Write coverage data in LCOV format. See man page for geninfo(1).
 void Shell::WriteLcovData(v8::Isolate* isolate, const char* file) {
   if (!file) return;
   HandleScope handle_scope(isolate);
-  debug::Coverage coverage = debug::Coverage::Collect(isolate, false);
+  debug::Coverage coverage = debug::Coverage::CollectPrecise(isolate);
   std::ofstream sink(file, std::ofstream::app);
   for (size_t i = 0; i < coverage.ScriptCount(); i++) {
     debug::Coverage::ScriptData script_data = coverage.GetScriptData(i);
     Local<debug::Script> script = script_data.GetScript();
     // Skip unnamed scripts.
     Local<String> name;
     if (!script->Name().ToLocal(&name)) continue;
     std::string file_name = ToSTLString(name);
     // Skip scripts not backed by a file.
     if (!std::ifstream(file_name).good()) continue;
@@ skipping 1344 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif