[Downloads] Use the initiating StoragePartition for resumption.

components/test/data/history/history.31.sql

 PRAGMA foreign_keys=OFF;
 BEGIN TRANSACTION;
 CREATE TABLE meta(key LONGVARCHAR NOT NULL UNIQUE PRIMARY KEY, value LONGVARCHAR);
-INSERT INTO "meta" VALUES('version','30');
+INSERT INTO "meta" VALUES('version','31');
 INSERT INTO "meta" VALUES('last_compatible_version','16');
 CREATE TABLE urls(id INTEGER PRIMARY KEY,url LONGVARCHAR,title LONGVARCHAR,visit_count INTEGER DEFAULT 0 NOT NULL,typed_count INTEGER DEFAULT 0 NOT NULL,last_visit_time INTEGER NOT NULL,hidden INTEGER DEFAULT 0 NOT NULL,favicon_id INTEGER DEFAULT 0 NOT NULL);
 CREATE TABLE visits(id INTEGER PRIMARY KEY,url INTEGER NOT NULL,visit_time INTEGER NOT NULL,from_visit INTEGER,transition INTEGER DEFAULT 0 NOT NULL,segment_id INTEGER,visit_duration INTEGER DEFAULT 0 NOT NULL);
 CREATE TABLE visit_source(id INTEGER PRIMARY KEY,source INTEGER NOT NULL);
 CREATE TABLE keyword_search_terms (keyword_id INTEGER NOT NULL,url_id INTEGER NOT NULL,lower_term LONGVARCHAR NOT NULL,term LONGVARCHAR NOT NULL);
-CREATE TABLE downloads (id INTEGER PRIMARY KEY,guid VARCHAR NOT NULL,current_path LONGVARCHAR NOT NULL,target_path LONGVARCHAR NOT NULL,start_time INTEGER NOT NULL,received_bytes INTEGER NOT NULL,total_bytes INTEGER NOT NULL,state INTEGER NOT NULL,danger_type INTEGER NOT NULL,interrupt_reason INTEGER NOT NULL,hash BLOB NOT NULL,end_time INTEGER NOT NULL,opened INTEGER NOT NULL,referrer VARCHAR NOT NULL,http_method VARCHAR NOT NULL,by_ext_id VARCHAR NOT NULL,by_ext_name VARCHAR NOT NULL,etag VARCHAR NOT NULL,last_modified VARCHAR NOT NULL,mime_type VARCHAR(255) NOT NULL,original_mime_type VARCHAR(255) NOT NULL);
+CREATE TABLE downloads (id INTEGER PRIMARY KEY,guid VARCHAR NOT NULL,current_path LONGVARCHAR NOT NULL,target_path LONGVARCHAR NOT NULL,start_time INTEGER NOT NULL,received_bytes INTEGER NOT NULL,total_bytes INTEGER NOT NULL,state INTEGER NOT NULL,danger_type INTEGER NOT NULL,interrupt_reason INTEGER NOT NULL,hash BLOB NOT NULL,end_time INTEGER NOT NULL,opened INTEGER NOT NULL,referrer VARCHAR NOT NULL,tab_url VARCHAR NOT NULL,tab_referrer_url VARCHAR NOT NULL,http_method VARCHAR NOT NULL,by_ext_id VARCHAR NOT NULL,by_ext_name VARCHAR NOT NULL,etag VARCHAR NOT NULL,last_modified VARCHAR NOT NULL,mime_type VARCHAR(255) NOT NULL,original_mime_type VARCHAR(255) NOT NULL);
 CREATE TABLE downloads_url_chains (id INTEGER NOT NULL,chain_index INTEGER NOT NULL,url LONGVARCHAR NOT NULL, PRIMARY KEY (id, chain_index) );
 CREATE TABLE segments (id INTEGER PRIMARY KEY,name VARCHAR,url_id INTEGER NON NULL);
 CREATE TABLE segment_usage (id INTEGER PRIMARY KEY,segment_id INTEGER NOT NULL,time_slot INTEGER NOT NULL,visit_count INTEGER DEFAULT 0 NOT NULL);
 CREATE INDEX visits_url_index ON visits (url);
 CREATE INDEX visits_from_index ON visits (from_visit);
 CREATE INDEX visits_time_index ON visits (visit_time);
 CREATE INDEX segments_name ON segments(name);
 CREATE INDEX segments_url_id ON segments(url_id);
 CREATE INDEX segment_usage_time_slot_segment_id ON segment_usage(time_slot, segment_id);
 CREATE INDEX segments_usage_seg_id ON segment_usage(segment_id);
 CREATE INDEX urls_url_index ON urls (url);
 CREATE INDEX keyword_search_terms_index1 ON keyword_search_terms (keyword_id, lower_term);
 CREATE INDEX keyword_search_terms_index2 ON keyword_search_terms (url_id);
 CREATE INDEX keyword_search_terms_index3 ON keyword_search_terms (term);
 COMMIT;