Add SetImageData api to chrome.clipboard.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 4b815f8e1d06f1b5bcb6dd4a5b89237642599d4e..73d76df1ae8cc2d1092e5fb4690401b49304631e 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -3891,6 +3891,12 @@ Data associated with this app will be removed from this device.
         <message name="IDS_EXTENSION_PROMPT_WARNING_CLIPBOARD" desc="Permission string for access to clipboard.">
           Read data you copy and paste
         </message>
+        <message name="IDS_EXTENSION_PROMPT_WARNING_CLIPBOARD_READWRITE" desc="Permission string for access to clipboard for read and write permission.">
+          Read and modify data you copy and paste
+        </message>
+        <message name="IDS_EXTENSION_PROMPT_WARNING_CLIPBOARD_WRITE" desc="Permission string for acess to clipboard for write permission.">
+          Modify data you copy and paste
+        </message>        
         <message name="IDS_EXTENSION_PROMPT_WARNING_DEBUGGER" desc="Permission string for access to debugger.">
           Access the page debugger backend
         </message>