Reland "[blink] Generate SyncToken in advance in RasterRecord()"

This is a reland of commit 329f4d03ec

The reverted commit did not contain issues by itself, but rather
exposed an existing issue where the sample coverage values may not
be properly set on Adreno drivers. The underlying issue was addressed
by https://crrev.com/c/6447878.

Original change's description:
> [blink] Generate SyncToken in advance in RasterRecord()
>
> Currently in RasterRecord(), WillDrawInternal() sets a boolean that,
> if true, will lead to the generation of a SyncToken at a later time.
> However, in order to apply scoped SyncToken access for raster, we need
> to ensure that the SyncToken's generation is localized inside
> RasterRecord().
>
> This CL is a step towards that purpose. We now generate the SyncToken
> right after the RasterRecordOOP() operation. This CL is not meant to
> cause any behavioral change.
>
> Bug: 40286368
> Change-Id: I8b8a0a121b5d2caef8722e4939669770775c86f2
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6426236
> Commit-Queue: Mingjing Zhang <mjzhang@chromium.org>
> Reviewed-by: Vasiliy Telezhnikov <vasilyt@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1442304}

Bug: 40286368
Change-Id: I16eaadddf0350a9f8e7d76807f38425eb0cf01a1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6517154
Reviewed-by: Vasiliy Telezhnikov <vasilyt@chromium.org>
Commit-Queue: Mingjing Zhang <mjzhang@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1456982}

third_party/blink/renderer/platform/graphics/canvas_resource_provider.cc

@@ -678,6 +678,7 @@ class CanvasResourceProviderSharedImage : public CanvasResourceProvider,
     is_cleared_ = true;
     RasterRecordOOP(std::move(last_recording), needs_clear,
                     resource()->GetClientSharedImage()->mailbox());
+    resource()->GetSyncToken();
   }
 
   bool ShouldReplaceTargetBuffer(