Change UseCounter number for EmbedElementWithoutTypeSrcChanged

The number I used when I just added this use counter, 3745, was already
being used by another usecounter that got deleted. You can see that it
shows the old name on chromestatus as well:
https://chromestatus.com/metrics/feature/timeline/popularity/3745

Bug: 1161163
Change-Id: I341b8727cdfea79539e2cc3448a8ec7076490ff8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2618999
Auto-Submit: Joey Arhar <jarhar@chromium.org>
Commit-Queue: Matt Falkenhagen <falken@chromium.org>
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841923}

third_party/blink/public/mojom/web_feature/web_feature.mojom

@@ -3064,10 +3064,10 @@ enum WebFeature {
   kCrossOriginSubframeWithoutEmbeddingControl = 3742,
   kReadableStreamWithByteSource = 3743,
   kReadableStreamBYOBReader = 3744,
-  kEmbedElementWithoutTypeSrcChanged = 3745,
   kSamePartyCookieAttribute = 3746,
   kSamePartyCookieExclusionOverruledSameSite = 3747,
   kSamePartyCookieInclusionOverruledSameSite = 3748,
+  kEmbedElementWithoutTypeSrcChanged = 3749,
 
   // Add new features immediately above this line. Don't change assigned
   // numbers of any item, and don't reuse removed slots.

third_party/blink/web_tests/plugins/embed-src-change-usecounter.html

@@ -7,6 +7,6 @@
 <script>
 test(() => {
   embedid.src = '../http/tests/resources/test.webm';
-  assert_true(internals.isUseCounted(document, 3745));
+  assert_true(internals.isUseCounted(document, 3749));
 }, 'Verifies that changing embed src gets use counted.');
 </script>

tools/metrics/histograms/enums.xml

@@ -30822,6 +30822,7 @@ Called by update_use_counter_feature_enum.py.-->
   <int value="3746" label="SamePartyCookieAttribute"/>
   <int value="3747" label="SamePartyCookieExclusionOverruledSameSite"/>
   <int value="3748" label="SamePartyCookieInclusionOverruledSameSite"/>
+  <int value="3749" label="EmbedElementWithoutTypeSrcChanged"/>
 </enum>
 
 <enum name="FeaturePolicyAllowlistType">