Reland of place system IO calls in chromecast/crash with Chrome utilities.

chromecast/crash/linux/minidump_generator.h

 // Copyright 2015 The Chromium 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 CHROMECAST_CRASH_LINUX_MINIDUMP_GENERATOR_H_
 #define CHROMECAST_CRASH_LINUX_MINIDUMP_GENERATOR_H_
 
 #include <string>
 
 namespace chromecast {
 
+// An interface to generate a minidump at a given filepath.
 class MinidumpGenerator {
  public:
   virtual ~MinidumpGenerator() {}
 
-  // Interface to generate a minidump file in given path.
-  // This is called inside MinidumpWriter::DoWorkLocked().
+  // Generates a minidump file at |minidump_path|. This method should only be
+  // called on a thread without IO restrictions, as non-trivial implementations
+  // will almost certainly require IO permissions. Returns true if minidump was
+  // successfully generated.
   virtual bool Generate(const std::string& minidump_path) = 0;
 };
 
 }  // namespace chromecast
 
 #endif  // CHROMECAST_CRASH_LINUX_MINIDUMP_GENERATOR_H_