Merge #1471

1471: Hardware Abstraction Layer r=msiglreith a=kvark

**Connections**
Closes #1423

**Description**
Prototyping the new hardware abstraction layer for wgpu, which replaces gfx-rs dependencies.
The central piece is "wgpu-hal/src/lib.rs".

### Metrics
| what                     | wgpu-core, LOC | graphics, LOC | Total | Build time |
| ----------------- | ----------------- | -------------- | ---- | ---------- |
| Old: _gfx-hal_      | 23K                       | 28K                 | **51K**  | 62s   |
| New: _wgpu-hal_ | 20.5K                    | 10.5K               | **31K** | 48s   |

### TODO:
- [x] wgpu-hal API
- [x] internal example/bench
- [x] Metal
- [x] Vulkan

**Testing**
examples


Co-authored-by: Dzmitry Malyshau <kvarkus@gmail.com>

.github/ISSUE_TEMPLATE/config.yml

@@ -4,5 +4,5 @@ contact_links:
     url: https://github.com/gfx-rs/naga/issues/new/choose
     about: Issues with or enhancements for the shader translation.
   - name: Question about wgpu
-    url: https://github.com/gfx-rs/wgpu-rs/discussions/new
+    url: https://github.com/gfx-rs/wgpu/discussions/new
     about: Any questions about how to use wgpu should go here.

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
 
   android_build:
     name: Android Stable
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     env:
       TARGET: aarch64-linux-android
       PKG_CONFIG_ALLOW_CROSS: 1
@@ -35,8 +35,9 @@ jobs:
         run: cargo check --manifest-path wgpu-core/Cargo.toml --features trace --target ${{ env.TARGET }}
 
   wasm:
+    if: false  # disable until hal/Gles backend is setup
     name: Web Assembly
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     env:
       RUSTFLAGS: --cfg=web_sys_unstable_apis
     steps:
@@ -53,7 +54,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [macos-10.15, ubuntu-18.04, windows-2019]
+        os: [macos-10.15, ubuntu-20.04, windows-2019]
         channel: [stable, nightly]
         include:
           - name: MacOS Stable
@@ -69,18 +70,18 @@ jobs:
             additional_core_features:
             additional_player_features:
           - name: Ubuntu Stable
-            os: ubuntu-18.04
+            os: ubuntu-20.04
             channel: stable
             prepare_command:
             additional_core_features: trace,replay
             additional_player_features:
           - name: Ubuntu Nightly
-            os: ubuntu-18.04
+            os: ubuntu-20.04
             channel: nightly
             prepare_command: |
               echo "Installing Vulkan"
               sudo apt-get update -y -qq
-              sudo add-apt-repository ppa:kisak/kisak-mesa -y
+              sudo add-apt-repository ppa:ubuntu-x-swat/updates -y
               sudo apt-get update
               sudo apt install -y libxcb-xfixes0-dev mesa-vulkan-drivers
             additional_core_features: serial-pass
@@ -123,7 +124,7 @@ jobs:
         run: cargo test -- --nocapture
 
   docs:
-    runs-on: [ubuntu-18.04]
+    runs-on: [ubuntu-latest]
     steps:
     - uses: actions/checkout@v2
     - name: Install latest nightly

CHANGELOG.md

@@ -1,7 +1,9 @@
 # Change Log
 
 TBD:
-  - Merged wgpu-rs and wgpu back into a single repository
+  - Crates:
+    - Merged wgpu-rs and wgpu back into a single repository
+    - Replaced gfx-rs dependencies by the new `wgpu-hal`
 
 ## v0.8 (2021-04-29)
   - Naga is used by default to translate shaders, SPIRV-Cross is optional behind `cross` feature