Use UtilityProcessHost to patch files.

chrome/common/chrome_utility_messages.h

Index: chrome/common/chrome_utility_messages.h
diff --git a/chrome/common/chrome_utility_messages.h b/chrome/common/chrome_utility_messages.h
index 2c2acbcb1b90f0fb0d20d9973bfbf6ae89491399..e1d367d8ba65eab0d6b966ab74ceba18bcf54902 100644
--- a/chrome/common/chrome_utility_messages.h
+++ b/chrome/common/chrome_utility_messages.h
@@ -142,7 +142,7 @@ IPC_STRUCT_TRAITS_END()
 // Utility process messages:
 // These are messages from the browser to the utility process.
 
-// Tell the utility process to unpack the given extension file in its
+// Tells the utility process to unpack the given extension file in its
 // directory and verify that it is valid.
 IPC_MESSAGE_CONTROL4(ChromeUtilityMsg_UnpackExtension,
                      base::FilePath /* extension_filename */,
@@ -205,6 +205,22 @@ IPC_MESSAGE_CONTROL1(ChromeUtilityMsg_GetPrinterCapsAndDefaults,
 IPC_MESSAGE_CONTROL1(ChromeUtilityMsg_GetPrinterSemanticCapsAndDefaults,
                      std::string /* printer name */)
 
+// Tell the utility process to patch the given |input_file| using |patch_file|
+// and place the output in |output_file|. The patch should use the bsdiff
+// algorithm (Courgette's version).
+IPC_MESSAGE_CONTROL3(ChromeUtilityMsg_PatchFileBsdiff,
+                     base::FilePath /* input_file */,
+                     base::FilePath /* patch_file */,
+                     base::FilePath /* output_file */)
+
+// Tell the utility process to patch the given |input_file| using |patch_file|
+// and place the output in |output_file|. The patch should use the Courgette
+// algorithm.
+IPC_MESSAGE_CONTROL3(ChromeUtilityMsg_PatchFileCourgette,
+                     base::FilePath /* input_file */,
+                     base::FilePath /* patch_file */,
+                     base::FilePath /* output_file */)
+
 #if defined(OS_CHROMEOS)
 // Tell the utility process to create a zip file on the given list of files.
 IPC_MESSAGE_CONTROL3(ChromeUtilityMsg_CreateZipFile,
@@ -379,6 +395,13 @@ IPC_MESSAGE_CONTROL2(
     printing::PrinterSemanticCapsAndDefaults)
 #endif
 
+// Reply when a file has been patched successfully.
+IPC_MESSAGE_CONTROL0(ChromeUtilityHostMsg_PatchFile_Succeeded)
+
+// Reply when patching a file failed.
+IPC_MESSAGE_CONTROL1(ChromeUtilityHostMsg_PatchFile_Failed,
+                     int /* error code */)
+
 // Reply when the utility process has failed to obtain the printer
 // capabilities and defaults.
 IPC_MESSAGE_CONTROL1(ChromeUtilityHostMsg_GetPrinterCapsAndDefaults_Failed,