Cherry-picks of multiple html CLs

Cherry-picks of multiple html CLs

The result of running

Update DDC libraries to match SDK, and debugger_test golden file
git cherry-pick  d60efa87fecf595a5bc62a730d61060552f4365e # https://codereview.chromium.org/2902973004 Obsolete test in svgelement_test
git cherry-pick b4b02daade289729cfffd84bab9dcfe9575876fe # https://codereview.chromium.org/2899173002  Include DDC fixes to dart:html in the main version
git cherry-pick bbfa1dac84980f0b0cb11cbe4b6591d6df43d52e # https://codereview.chromium.org/2903143002  Update lib_strong status for passing svg_element_test
git cherry-pick 0bb2d5e548e8ab40374f64a37c5951905215b0b5 # https://codereview.chromium.org/2899083007  Update DDC html libraries to match SDK
git checkout master pkg/dev_compiler/lib
git commit
git cherry-pick 6f71f9c80b2088df5afa5e8ded7196db120f5b18 # https://codereview.chromium.org/2907563003  Revert "[Experiment] Stop suppressing DragEvent"
git cherry-pick 20dc74984432702dd6de679383c4cea8e0e31e3e # https://codereview.chromium.org/2901213006  Suppress Scale interface - unused.
git cherry-pick d21cc80a5457e68bcd3af4b6b5106e0f08a1ee3b # https://codereview.chromium.org/2899393004  Add a dataTransfer member to MouseEvent
git cherry-pick a865f0ecf225fbffaf393f7b55c715aa64d090b6 # https://codereview.chromium.org/2903333002  Update DDC libraries to match SDK, and debugger_test golden file
cd pkg/dev_compiler
tool/build_sdk.sh

BUG=
R=jacobr@google.com

Review-Url: https://codereview.chromium.org/2903333002 .

Add a dataTransfer member to MouseEvent

BUG=
R=terry@google.com

Review-Url: https://codereview.chromium.org/2899393004 .

Suppress Scale interface - unused.

TBR=alanknight@google.com

Review-Url: https://codereview.chromium.org/2901213006 .

Revert "[Experiment] Stop suppressing DragEvent"

This reverts commit fbbb97467030db2f0996e19f3c5bc133851dee31.

Also updates the cached_patches.dart file.

BUG=
R=terry@google.com

Review-Url: https://codereview.chromium.org/2907563003 .

Update DDC html libraries to match SDK

BUG=
R=vsm@google.com

Review-Url: https://codereview.chromium.org/2899083007 .

Update lib_strong status for passing svg_element_test

BUG=

Review-Url: https://codereview.chromium.org/2903143002 .

Include DDC fixes to dart:html in the main version

BUG=
R=jacobr@google.com, vsm@google.com

Review-Url: https://codereview.chromium.org/2899173002 .

Remove obsolete test in svgelement_test

BUG=

Review-Url: https://codereview.chromium.org/2902973004 .