Type conversion fixes, tools/ edition.

This is mostly to fix MSVC warnings about possible value truncation.

BUG=81439
TEST=none

Review URL: https://codereview.chromium.org/644433003

Cr-Commit-Position: refs/heads/master@{#300131}

tools/gn/command_gen.cc

@@ -114,7 +114,7 @@ int RunGen(const std::vector<std::string>& args) {
         base::IntToString(
             setup->scheduler().input_file_manager()->GetInputFileCount()) +
         " files in " +
-        base::IntToString(elapsed_time.InMilliseconds()) + "ms\n";
+        base::Int64ToString(elapsed_time.InMilliseconds()) + "ms\n";
     OutputString(stats);
   }
 

tools/gn/filesystem_utils.cc

@@ -132,7 +132,8 @@ std::vector<base::FilePath::StringType> GetPathComponents(
   // don't want the slash in there. This doesn't support input like "C:foo"
   // which means foo relative to the current directory of the C drive but
   // that's basically legacy DOS behavior we don't need to support.
-  if (result.size() >= 2 && result[1].size() == 1 && IsSlash(result[1][0]))
+  if (result.size() >= 2 && result[1].size() == 1 &&
+      IsSlash(static_cast<char>(result[1][0])))
     result.erase(result.begin() + 1);
 #endif
 

tools/gn/generate_test_gn_data.cc

@@ -38,7 +38,7 @@ base::FilePath RepoPathToPathName(const std::vector<int>& repo_path) {
 
 std::string TargetIndexToLetter(int target_index) {
   char ret[2];
-  ret[0] = 'a' + target_index;
+  ret[0] = static_cast<char>('a' + target_index);
   ret[1] = 0;
   return ret;
 }

tools/gn/trace.cc

@@ -220,7 +220,7 @@ std::string SummarizeTraces() {
   // possible for more than one to run if more than one build is going in
   // parallel. Just report the total of all of them.
   if (!check_headers.empty()) {
-    float check_headers_time = 0;
+    double check_headers_time = 0;
     for (const auto& cur : check_headers)
       check_headers_time += cur->delta().InMillisecondsF();