lib: fix to add resolve() before return at Blob.stream()'s source.pull()

Add lacked calling resolve() for finish ReadableStream source.pull().

Fixes: nodejs#48668
Fixes: nodejs#48916
Fixes: nodejs#48232
Refs: nodejs@8cc1438

lib/internal/blob.js

@@ -360,6 +360,11 @@ class Blob {
             queueMicrotask(() => {
               if (c.desiredSize <= 0) {
                 // A manual backpressure check.
+                if (this.pendingPulls.length !== 0) {
+                  // A case of waiting pull finished (= not yet canceled)
+                  const pending = this.pendingPulls.shift();
+                  pending.resolve();
+                }
                 return;
               }
               readNext();

test/parallel/test-blob.js

@@ -269,6 +269,29 @@ assert.throws(() => new Blob({}), {
   reader.closed.then(common.mustCall());
 })().then(common.mustCall());
 
+(async () => {
+  const b = new Blob(['A', 'B', 'C']);
+  const stream = b.stream();
+  const chunks = [];
+  const decoder = new TextDecoder();
+  await stream.pipeTo(new WritableStream({
+    write(chunk) {
+      chunks.push(decoder.decode(chunk, { stream: true }));
+    }
+  }));
+  assert.strictEqual(chunks.join(''), 'ABC');
+})().then(common.mustCall());
+
+(async () => {
+  const file = new Blob(['<svg></svg>'], { type: 'image/svg+xml' });
+  const url = URL.createObjectURL(file);
+  const res = await fetch(url);
+  const blob = await res.blob();
+  assert.strictEqual(blob.size, 11);
+  assert.strictEqual(blob.type, 'image/svg+xml');
+  assert.strictEqual(await blob.text(), '<svg></svg>');
+})().then(common.mustCall());
+
 (async () => {
   const b = new Blob(Array(10).fill('hello'));
   const stream = b.stream();