workflow: Simplify cacheing into one workflow

Author: alexytomi

.github/workflows/build.yml

@@ -9,6 +9,41 @@ on:
   workflow_dispatch:
 
 jobs:
+  restore-build-environment:
+    runs-on: ubuntu-24.04
+    steps:
+        - name: Restore environment from cache
+          id: cached-environment-restore
+          uses: actions/cache/save@v4
+          with:
+            path: ./
+            key: ios_and_android-build-environment
+        - name: Setup environment if cache not found
+          if: steps.cached-environment-restore.outputs.cache-hit != 'true'
+          run: |
+            if [ ! -d "depot_tools" ] ; then
+            git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
+            fi
+            echo "$PWD/depot_tools" >> $GITHUB_PATH
+            export PATH="$PWD/depot_tools:$PATH"
+            gclient config --spec 'solutions = [
+              {
+                "name": ".",
+                "url": "https://chromium.googlesource.com/angle/angle.git",
+                "deps_file": "DEPS",
+                "managed": False,
+                "custom_vars": {},
+              },
+            ]
+            target_os = ["ios", "android"]'
+            gclient sync -Rf --no-history --with_branch_heads
+        - name: Save environment to cache
+          if: steps.cached-environment-restore.outputs.cache-hit != 'true'
+          uses: actions/cache/save@v4
+          with:
+            path: ./
+            key: ios_and_android-build-environment
+
   build:
     strategy:
       matrix:
@@ -32,50 +67,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
-      - name: Cache third_party/llvm
-        uses: actions/cache@v4
-        with:
-          path: third_party/llvm
-          key: third_party-llvm
-      - name: Cache third_party/VK-GL-CTS
-        uses: actions/cache@v4
-        with:
-          path: third_party/VK-GL-CTS
-          key: third_party-VK-GL-CTS
-      - name: Cache third_party/SwiftShader
-        uses: actions/cache@v4
-        with:
-          path: third_party/SwiftShader
-          key: third_party-SwiftShader
-      - name: Cache third_party/dawn
-        uses: actions/cache@v4
-        with:
-          path: third_party/dawn
-          key: third_party-dawn
-      - name: Cache depot_tools
-        uses: actions/cache@v4
-        with:
-          path: depot_tools
-          key: depot-tools
-# This should only be rarely ran so its here so the cache priority still is somewhat biggest to smallest
-      - name: Install depot_tools
-        run: |
-          if [ ! -d "depot_tools" ] ; then
-          git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
-          fi
-          echo "$PWD/depot_tools" >> $GITHUB_PATH
-      - name: Cache tools
-        uses: actions/cache@v4
-        with:
-          path: tools
-          key: tools
-      - name: Cache build
-        uses: actions/cache@v4
-        with:
-          path: build
-          key: build
 
-      - name: Fetch ANGLE and dependencies
+      - name: Fetch and verify ANGLE dependencies
         run: |
           gclient config --spec 'solutions = [
             {