[FileBrowser] Added DefaultAction dialog to choose default action.

chrome/common/extensions/api/file_browser_private.json

Index: chrome/common/extensions/api/file_browser_private.json
diff --git a/chrome/common/extensions/api/file_browser_private.json b/chrome/common/extensions/api/file_browser_private.json
index 3b28fd858ec4762d822e0cb9e2591af64c7a31e3..e3e9f3b790200eeaa59805ead4bf70bab471697f 100644
--- a/chrome/common/extensions/api/file_browser_private.json
+++ b/chrome/common/extensions/api/file_browser_private.json
@@ -388,6 +388,30 @@
         ]
       },
       {
+        "name": "setDefaultTask",
+        "description": "Sets default task.",
+        "parameters": [
+          {
+            "name": "taskId",
+            "type": "string",
+            "description": "The unique identifier of task to mark as default."
+          },
+          {
+            "name": "callback",
+            "type": "function",
+            "optional": true,
+            "parameters": [
+              {
+                "name": "success",
+                "type": "boolean",
+                "optional": true,

[asargent_no_longer_on_chrome, 2012/05/22 16:46:24]

nit: I'm not sure of your use cases, but it seems like you'd want this boolean
to be non-optional, since making the task default either succeeded or it didn't.
"Do or do not, there is no try" as Yoda says.

Also, if you wanted you could forgo having the explicit boolean for success
altogether, and instead just set chrome.extension.lastError (by returning false
instead of true from your ExtensionFunction subclass in the browser process) if
the call failed for some reason.

+                "description": "True if task successfully made default."
+              }
+            ]
+          }
+        ]        
+      },
+      {
         "name": "getFileTasks",
         "description": "Gets the list of tasks that can be performed over selected files.",
         "parameters": [