Remove redundant c_str() calls.

chrome/browser/component_updater/pnacl_component_installer.cc

Index: chrome/browser/component_updater/pnacl_component_installer.cc
diff --git a/chrome/browser/component_updater/pnacl_component_installer.cc b/chrome/browser/component_updater/pnacl_component_installer.cc
index f3b747b42615421a323f39ba5920a63ab4102757..69d6e93ac722c1b98d550d0d33dd2a6504dd216f 100644
--- a/chrome/browser/component_updater/pnacl_component_installer.cc
+++ b/chrome/browser/component_updater/pnacl_component_installer.cc
@@ -182,7 +182,7 @@ bool CheckPnaclComponentManifest(const base::DictionaryValue& manifest,
     LOG(WARNING) << "'version' field is missing from manifest!";
     return false;
   }
-  base::Version version(proposed_version.c_str());
+  base::Version version(proposed_version);
   if (!version.IsValid()) {
     LOG(WARNING) << "'version' field in manifest is invalid "
                  << version.GetString();