Remove extension process side of chrome.devtools API, it's obsolete.

chrome/common/extensions_api_resources.grd

Index: chrome/common/extensions_api_resources.grd
diff --git a/chrome/common/extensions_api_resources.grd b/chrome/common/extensions_api_resources.grd
index 7c34d5f96d54c1ab4ff637f03f6e4b944b8b4333..5c4f07a5e8025ad7091799bb0f5cdc131272231b 100644
--- a/chrome/common/extensions_api_resources.grd
+++ b/chrome/common/extensions_api_resources.grd
@@ -15,7 +15,6 @@
       <include name="IDR_EXTENSION_API_JSON_COMMANDS" file="extensions\api\commands.json" type="BINDATA" />
       <include name="IDR_EXTENSION_API_JSON_DECLARATIVE_CONTENT" file="extensions\api\declarative_content.json" type="BINDATA" />
       <include name="IDR_EXTENSION_API_JSON_DECLARATIVE_WEBREQUEST" file="extensions\api\declarative_web_request.json" type="BINDATA" />
-      <include name="IDR_EXTENSION_API_JSON_DEVTOOLS" file="extensions\api\devtools.json" type="BINDATA" />
       <include name="IDR_EXTENSION_API_JSON_ECHOPRIVATE" file="extensions\api\echo_private.json" type="BINDATA" />
       <include name="IDR_EXTENSION_API_JSON_EXPERIMENTAL_INPUT_VIRTUALKEYBOARD" file="extensions\api\experimental_input_virtual_keyboard.json" type="BINDATA" />
       <include name="IDR_EXTENSION_API_JSON_EXPERIMENTAL_PROCESSES" file="extensions\api\experimental_processes.json" type="BINDATA" />