Wrap large IndexedDB values into Blobs before writing to LevelDB.

third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support-promises.js

Index: third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support-promises.js
diff --git a/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support-promises.js b/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support-promises.js
index 0762a8d7e9c1a664d68b79e96b20fbafad883944..21e2163ec60eb3eee05269b83f583f77fad780eb 100644
--- a/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support-promises.js
+++ b/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support-promises.js
@@ -270,3 +270,23 @@ function checkTitleIndexContents(testCase, index, errorMessage) {
     assert_equals(result.author, BOOKS_RECORD_DATA[2].author, errorMessage);
   });
 }
+
+// Returns an Uint8Array with pseudorandom data.
+//
+// The PRNG should be sufficient to defeat compression schemes, but it is not
+// cryptographically strong.
+function largeValue(size, seed) {
+  const buffer = new Uint8Array(size);
+
+  // 32-bit xorshift - the seed can't be zero
+  let state = 1000 + seed;
+
+  for (let i = 0; i < size; ++i) {
+    state ^= state << 13;
+    state ^= state >> 17;
+    state ^= state << 5;
+    buffer[i] = state & 0xff;
+  }
+
+  return buffer;
+}