…eviewers,nical

Differential Revision: https://phabricator.services.mozilla.com/D65805

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/a561435c24cf70d2e491f2a7cde699bebdaaad97

… feGaussianBlur-5-ref.svg CLOSED TREE

Backed out changeset a561435c24cf (bug 1618000)
Backed out changeset e720691ccf17 (bug 1618000)

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/9c027d62be503fe8c584e02d65fd57246900063d

Differential Revision: https://phabricator.services.mozilla.com/D65591

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/87ddcdfc5fcffbeb745fe260e4ef08af6a4b823f

Differential Revision: https://phabricator.services.mozilla.com/D65593

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/419105739e539782089163e399c41bf90e8ee2ea

…nterop with SWGL. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D65595

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/54ec5a6e8e457950f10a4d0b1fceec5f5644048c

… r=gw,kvark

Differential Revision: https://phabricator.services.mozilla.com/D65596

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/bd8ba66dc2ac162c550848bfef50b1f09917658d

…to minimize memory churn. r=gw

Differential Revision: https://phabricator.services.mozilla.com/D65598

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/375896f494ae77bb7bfa23abf8e31f49ba1aef86

Differential Revision: https://phabricator.services.mozilla.com/D65602

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/76f80dce8875c41843cbd515b00785f78be083c6

…lower there. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D65613

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/30b28118362a03b07d5698a6526caf155e7a17d1

…rmuizel,gw

Add annotations to vertex shaders so that SWGL can detect when a vertex attribute
is generated by per-instance data rather than per-vertex data.

Differential Revision: https://phabricator.services.mozilla.com/D65614

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/ad7f43d72b08243106fddc460f2205926d4f87bf

…t. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D65615

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/9b1360daa75acf0f79edb3df93395a6b5890ce3b

Backed out changeset 29f9f745ff65 (bug 1612941)
Backed out changeset d92e03315f8d (bug 1612941)
Backed out changeset 9b1360daa75a (bug 1612941)
Backed out changeset ad7f43d72b08 (bug 1612941)
Backed out changeset 30b28118362a (bug 1612941)
Backed out changeset 76f80dce8875 (bug 1612941)
Backed out changeset 375896f494ae (bug 1612941)
Backed out changeset bd8ba66dc2ac (bug 1612941)
Backed out changeset 54ec5a6e8e45 (bug 1612941)
Backed out changeset 419105739e53 (bug 1612941)
Backed out changeset c198dedeaa1b (bug 1612941)
Backed out changeset 87ddcdfc5fcf (bug 1612941)

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/1b8df9d39a0fc712b6f8ca07865b578f1e724fae

Differential Revision: https://phabricator.services.mozilla.com/D65591

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/60151122db4de10a2fb9d346eb9104a9cba99341

Differential Revision: https://phabricator.services.mozilla.com/D65593

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/f94d5c7cee41c6cc24919cd63dad771b9cb65d2e

…nterop with SWGL. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D65595

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/edfca567651347492caaf427252f6821e5d2fd1b

… r=gw,kvark

Differential Revision: https://phabricator.services.mozilla.com/D65596

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/3cae17a5ec80e4ee12fe173a414fcd5eb46f9a41

…to minimize memory churn. r=gw

Differential Revision: https://phabricator.services.mozilla.com/D65598

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/dd1a92041bb4eaf550fab7404aa04ad80d0c60ae

Differential Revision: https://phabricator.services.mozilla.com/D65602

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/2d6f65fe6ec077935410a24132498cd9077316b7

…lower there. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D65613

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/ec0fffd12dec0b559eca792450521f671ae707b4

…rmuizel,gw

Add annotations to vertex shaders so that SWGL can detect when a vertex attribute
is generated by per-instance data rather than per-vertex data.

Differential Revision: https://phabricator.services.mozilla.com/D65614

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/2e0c9b9bd50759b80c9075c4ebb795a2031d4c35

…t. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D65615

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/c02c4c5bf7f7fd0d93f1df8661a42859eca2bf62

Differential Revision: https://phabricator.services.mozilla.com/D65617

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/bbb8ec38f3549d932c4cac2e11f0f76a8ffc7cd7

…CLOSED TREE

Backed out changeset bbb8ec38f354 (bug 1612941)
Backed out changeset cd798d2a0433 (bug 1612941)
Backed out changeset c02c4c5bf7f7 (bug 1612941)
Backed out changeset 2e0c9b9bd507 (bug 1612941)
Backed out changeset ec0fffd12dec (bug 1612941)
Backed out changeset 2d6f65fe6ec0 (bug 1612941)
Backed out changeset dd1a92041bb4 (bug 1612941)
Backed out changeset 3cae17a5ec80 (bug 1612941)
Backed out changeset edfca5676513 (bug 1612941)
Backed out changeset f94d5c7cee41 (bug 1612941)
Backed out changeset 67bba000daba (bug 1612941)
Backed out changeset 60151122db4d (bug 1612941)

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/005382a5a58ff70933c9f535b3a8e6158ccccea6

[import_pr] From #3875

Differential Revision: https://phabricator.services.mozilla.com/D66064

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/ab8746bb808719748e77de3d8ba538574bceee8c

DisplayItemBuilder now has methods:
```
void StartGroup(nsPaintedDisplayItem* aItem);
void CancelGroup();
void FinishGroup();
bool ReuseItem(nsPaintedDisplayItem* aItem);
```
WebRender display items previously created between calls to StartGroup() and FinishGroup() will be reused by a call to ReuseItem(),
which will push DisplayItem::ReuseItem(key) to WR display list, if the Gecko display item has been retained and reused.
Calling CancelGroup() will discard the display items that have been pushed after calling StartGroup().

For example, inside nsDisplayBackgroundColor::CreateWebRenderCommands():
```
aBuilder.StartGroup(this);
aBuilder.PushRect(r, r, !BackfaceIsHidden(),
                  wr::ToColorF(ToDeviceColor(mColor)));
aBuilder.FinishGroup();
```

Differential Revision: https://phabricator.services.mozilla.com/D65356

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/91760460f91496fb2262242dcdf7c0deb311978c

… a CLOSED TREE

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/b3d8484a2aaa21f511f43d1b1e42178e5efb2298

DisplayItemBuilder now has methods:
```
void StartGroup(nsPaintedDisplayItem* aItem);
void CancelGroup();
void FinishGroup();
bool ReuseItem(nsPaintedDisplayItem* aItem);
```
WebRender display items previously created between calls to StartGroup() and FinishGroup() will be reused by a call to ReuseItem(),
which will push DisplayItem::ReuseItem(key) to WR display list, if the Gecko display item has been retained and reused.
Calling CancelGroup() will discard the display items that have been pushed after calling StartGroup().

For example, inside nsDisplayBackgroundColor::CreateWebRenderCommands():
```
aBuilder.StartGroup(this);
aBuilder.PushRect(r, r, !BackfaceIsHidden(),
                  wr::ToColorF(ToDeviceColor(mColor)));
aBuilder.FinishGroup();
```

Differential Revision: https://phabricator.services.mozilla.com/D65356

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/f792d895cdf8f3819b987389301e98b5873123d8