Revert of Replace system IO calls in chromecast/crash with Chrome utilities.

chromecast/crash/linux/dummy_minidump_generator.h

Index: chromecast/crash/linux/dummy_minidump_generator.h
diff --git a/chromecast/crash/linux/dummy_minidump_generator.h b/chromecast/crash/linux/dummy_minidump_generator.h
index 5eabca8039bf704d070889518b4f4f6dbd5f2372..eb0312500357615dba713625522bc746dc9e5e49 100644
--- a/chromecast/crash/linux/dummy_minidump_generator.h
+++ b/chromecast/crash/linux/dummy_minidump_generator.h
@@ -21,12 +21,22 @@
   explicit DummyMinidumpGenerator(const std::string& existing_minidump_path);
 
   // MinidumpGenerator implementation:
-  // Moves the minidump located at |existing_minidump_path_| to |minidump_path|.
-  // Returns true if successful, false otherwise. Note that this function MUST
-  // be called on a thread without IO restrictions, or it will fail fatally.
   bool Generate(const std::string& minidump_path) override;
 
+  // Provide access to internal utility for testing.
+  bool CopyAndDeleteForTest(const std::string& dest_path) {
+    return CopyAndDelete(dest_path);
+  }
+
  private:
+  // Copies the contents of the file at |existing_minidump_path_| to the file at
+  // |dest_path|. If the copy operation succeeds, delete the file at
+  // |existing_minidump_path_|. Returns false if |existing_minidump_path_| can't
+  // be opened, or if the copy operation fails. Ideally, we would use Chrome
+  // utilities for a task like this, but we must ensure that this operation can
+  // occur on any thread (regardless of IO restrictions).
+  bool CopyAndDelete(const std::string& dest_path);
+
   const std::string existing_minidump_path_;
 
   DISALLOW_COPY_AND_ASSIGN(DummyMinidumpGenerator);