Files.app: Add an private API to get a download URL

chrome/browser/drive/drive_api_service.cc

Index: chrome/browser/drive/drive_api_service.cc
diff --git a/chrome/browser/drive/drive_api_service.cc b/chrome/browser/drive/drive_api_service.cc
index 11755c265a1380598df1f20b91698ae972f17a82..13f7df6bfb39b9f2421b4274a19f6ffbdef126c8 100644
--- a/chrome/browser/drive/drive_api_service.cc
+++ b/chrome/browser/drive/drive_api_service.cc
@@ -44,7 +44,7 @@ using google_apis::GDATA_PARSE_ERROR;
 using google_apis::GDataErrorCode;
 using google_apis::GetContentCallback;
 using google_apis::GetResourceEntryRequest;
-using google_apis::GetShareUrlCallback;
+using google_apis::GetUrlCallback;
 using google_apis::HTTP_NOT_IMPLEMENTED;
 using google_apis::HTTP_SUCCESS;
 using google_apis::InitiateUploadCallback;
@@ -101,7 +101,7 @@ const int kMaxNumFilesResourcePerRequestForSearch = 100;
 const char kAboutResourceFields[] =
     "kind,quotaBytesTotal,quotaBytesUsed,largestChangeId,rootFolderId";
 const char kFileResourceFields[] =
-    "kind,id,title,createdDate,sharedWithMeDate,mimeType,"
+    "kind,id,title,createdDate,sharedWithMeDate,downloadUrl,mimeType,"
     "md5Checksum,fileSize,labels/trashed,imageMediaMetadata/width,"
     "imageMediaMetadata/height,imageMediaMetadata/rotation,etag,"
     "parents(id,parentLink),alternateLink,"
@@ -109,13 +109,13 @@ const char kFileResourceFields[] =
 const char kFileResourceOpenWithLinksFields[] =
     "kind,id,openWithLinks/*";
 const char kFileListFields[] =
-    "kind,items(kind,id,title,createdDate,sharedWithMeDate,"
+    "kind,items(kind,id,title,createdDate,sharedWithMeDate,downloadUrl,"

[kinaba, 2014/07/09 06:02:48]

If we don't store downloadUrl in ResourceMetadata DB,
I think we can omit including the field in FileList and ChangeList.

Well, but on the other hand, if this inclusion does not affect performance, we
should not add divergence. @hashimoto, do you have any thoughts?

[hashimoto, 2014/07/09 07:48:57]

When last time I investigated this, "downloadUrl" was one of the "slow" fields
which makes the request about 50% slower.

But today it seems "downloadUrl" does not affect the performance much.
https://docs.google.com/spreadsheets/d/1Gi2NcoTkTfNjY8HYSuAjVZPj3BKTXkki2y4yI...

Getting a FileList with 300 entries takes 1.7 seconds both with and without
"downloadUrl".
Maybe the Drive server implementation has improved since then?

     "mimeType,md5Checksum,fileSize,labels/trashed,imageMediaMetadata/width,"
     "imageMediaMetadata/height,imageMediaMetadata/rotation,etag,"
     "parents(id,parentLink),alternateLink,"
     "modifiedDate,lastViewedByMeDate,shared),nextLink";
 const char kChangeListFields[] =
-    "kind,items(file(kind,id,title,createdDate,sharedWithMeDate,"
+    "kind,items(file(kind,id,title,createdDate,sharedWithMeDate,downloadUrl,"

[kinaba, 2014/07/09 06:02:48]

ditto

     "mimeType,md5Checksum,fileSize,labels/trashed,imageMediaMetadata/width,"
     "imageMediaMetadata/height,imageMediaMetadata/rotation,etag,"
     "parents(id,parentLink),alternateLink,modifiedDate,"
@@ -360,10 +360,9 @@ CancelCallback DriveAPIService::GetFileResource(
   return sender_->StartRequestWithRetry(request);
 }
 
-CancelCallback DriveAPIService::GetShareUrl(
-    const std::string& resource_id,
-    const GURL& embed_origin,
-    const GetShareUrlCallback& callback) {
+CancelCallback DriveAPIService::GetShareUrl(const std::string& resource_id,
+                                            const GURL& embed_origin,
+                                            const GetUrlCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());