Add build variant for go-specific recents.

This CL sets up the source directories to build a Go version of
quickstep recents/icon recents. This is accomplished by splitting the
quickstep resources/sources into two groups: the base source and
sources that should be overridden (recents_ui_overrides). The new Go
recents variant then takes the base and combines it with the sources
in go/quickstep which should replace the ones in recents_ui_overrides.

As of now, no classes have been moved yet, so there
are only placeholder files.

In addition, this modifies the make and gradle files to reflect the new
sources.

Bug: 114136250
Test: build all targets via tapas, build all APKs from IDE
Change-Id: I6d0a4d93ab1c38d4ffc28fd21823caadd96d23f7
diff --git a/build.gradle b/build.gradle
index e40df06..4191d47 100644
--- a/build.gradle
+++ b/build.gradle
@@ -59,6 +59,12 @@
             minSdkVersion 28
         }
 
+        withQuickstepIconRecents {
+            dimension "recents"
+
+            minSdkVersion 28
+        }
+
         withoutQuickstep {
             dimension "recents"
         }
@@ -67,7 +73,12 @@
     // Disable release builds for now
     android.variantFilter { variant ->
         if (variant.buildType.name.endsWith('release')) {
-            variant.setIgnore(true);
+            variant.setIgnore(true)
+        }
+
+        // Icon recents is Go only
+        if (name.contains("WithQuickstepIconRecents") && !name.contains("l3go")) {
+            variant.setIgnore(true)
         }
     }
 
@@ -112,8 +123,14 @@
         }
 
         withQuickstep {
-            res.srcDirs = ['quickstep/res']
-            java.srcDirs = ['quickstep/src']
+            res.srcDirs = ['quickstep/res', 'quickstep/recents_ui_overrides/res']
+            java.srcDirs = ['quickstep/src', 'quickstep/recents_ui_overrides/src']
+            manifest.srcFile "quickstep/AndroidManifest.xml"
+        }
+
+        withQuickstepIconRecents {
+            res.srcDirs = ['quickstep/res', 'go/quickstep/res']
+            java.srcDirs = ['quickstep/src', 'go/quickstep/src']
             manifest.srcFile "quickstep/AndroidManifest.xml"
         }
     }
@@ -136,6 +153,9 @@
     // Recents lib dependency
     withQuickstepImplementation fileTree(dir: "quickstep/libs", include: 'sysui_shared.jar')
 
+    // Recents lib dependency for Go
+    withQuickstepIconRecentsImplementation fileTree(dir: "quickstep/libs", include: 'sysui_shared.jar')
+
     // Required for AOSP to compile. This is already included in the sysui_shared.jar
     withoutQuickstepImplementation fileTree(dir: "libs", include: 'plugin_core.jar')