Add MediaStore.ACTION_PICK_IMAGES

The CL introduces a new public intent action to open the Photo Picker.
Apps can request this new intent action to launch photo picker and get
user selected images and videos.

Default behaviour for intent action sent with no additional extras or
inputs is picker shows all images and videos.
Input:
* MIME type: MIME type that the caller is interested in.
* EXTRA_ALLOW_MULTIPLE: If caller expects multiple selection
* EXTRA_PICK_IMAGES_MIN/EXTRA_PICK_IMAGES_MAX: If caller needs to
constrain on number of items that can/should be returned.
Output:
MediaStore URI(s) of selected item(s). The caller gets read access for
selected items without any storage permission.

Bug: 185228105
Test: Verified locally that we are able to launch picker with the new
intent action.

Change-Id: I93f8c73d019e620d7e2c3cd12282a7244adc17ce
2 files changed