Support stack_unwinder module in renderer process with isolated splits

This change moves the stack_unwinder module back out into a DFM since it
has no deps on //chrome Java code. After this change, module installer
can handle loading Java modules from isolated splits (although assets
will still take more work). Native libs are still in the base module, so
nothing special needs to be done there.

Bug: 1142967
Change-Id: I1af06b3153472581e058f606937de4e32f6a14ef
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2503581Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821618}

chrome/android/BUILD.gn

@@ -295,7 +295,6 @@ android_library("chrome_java") {
     "//chrome/android/modules/cablev2_authenticator/public:java",
     "//chrome/android/modules/image_editor/provider:java",
     "//chrome/android/modules/image_editor/public:java",
-    "//chrome/android/modules/stack_unwinder/provider:java",
     "//chrome/android/third_party/compositor_animator:compositor_animator_java",
     "//chrome/android/webapk/libs/client:client_java",
     "//chrome/android/webapk/libs/common:common_java",
@@ -2143,6 +2142,9 @@ android_library("base_module_java") {
     "//components/viz/service:service_java",
     "//content/public/android:content_java",
 
+    # Deps for DFMs.
+    "//chrome/android/modules/stack_unwinder/provider:java",
+
     # Deps to pull services into base module.
     # TODO(crbug.com/1126301): Consider moving these to the chrome module to
     # reduce base dex size.

chrome/android/modules/stack_unwinder/stack_unwinder_module.gni

@@ -10,4 +10,5 @@ stack_unwinder_module_desc = {
   java_deps = [ "//chrome/android/modules/stack_unwinder/internal:java" ]
   native_deps = [ "//chrome/android/modules/stack_unwinder/internal:native" ]
   load_native_on_get_impl = false
+  supports_isolated_split = true
 }

components/module_installer/android/java/src/org/chromium/components/module_installer/builder/Module.java

@@ -4,6 +4,8 @@
 
 package org.chromium.components.module_installer.builder;
 
+import android.content.Context;
+
 import androidx.annotation.VisibleForTesting;
 
 import org.chromium.base.BundleUtils;
@@ -107,7 +109,7 @@ public class Module<T> {
                 ensureNativeLoaded();
             }
 
-            mImpl = mInterfaceClass.cast(instantiateReflectively(mImplClassName));
+            mImpl = mInterfaceClass.cast(instantiateReflectively(mName, mImplClassName));
             return mImpl;
         }
     }
@@ -160,7 +162,7 @@ public class Module<T> {
         }
 
         return (ModuleDescriptor) instantiateReflectively(
-                "org.chromium.components.module_installer.builder.ModuleDescriptor_" + name);
+                name, "org.chromium.components.module_installer.builder.ModuleDescriptor_" + name);
     }
 
     /**
@@ -169,15 +171,17 @@ public class Module<T> {
      * Ignores strict mode violations since accessing code in a module may cause its DEX file to be
      * loaded and on some devices that can cause such a violation.
      *
+     * @param moduleName The module's name.
      * @param className The object's class name.
      * @return The object.
      */
-    private static Object instantiateReflectively(String className) {
+    private static Object instantiateReflectively(String moduleName, String className) {
+        Context context = ContextUtils.getApplicationContext();
+        if (BundleUtils.isIsolatedSplitInstalled(context, moduleName)) {
+            context = BundleUtils.createIsolatedSplitContext(context, moduleName);
+        }
         try (StrictModeContext ignored = StrictModeContext.allowDiskReads()) {
-            return ContextUtils.getApplicationContext()
-                    .getClassLoader()
-                    .loadClass(className)
-                    .newInstance();
+            return context.getClassLoader().loadClass(className).newInstance();
         } catch (Exception e) {
             throw new RuntimeException(e);
         }

components/module_installer/android/java/src/org/chromium/components/module_installer/builder/ModuleEngine.java

@@ -6,6 +6,7 @@ package org.chromium.components.module_installer.builder;
 
 import android.app.Activity;
 
+import org.chromium.base.BundleUtils;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.StrictModeContext;
 import org.chromium.components.module_installer.engine.EngineFactory;
@@ -39,6 +40,12 @@ class ModuleEngine implements InstallEngine {
 
     @Override
     public boolean isInstalled(String moduleName) {
+        // If the module is in an installed isolated split, it is installed.
+        if (BundleUtils.isIsolatedSplitInstalled(
+                    ContextUtils.getApplicationContext(), moduleName)) {
+            return true;
+        }
+
         // Accessing classes in the module may cause its DEX file to be loaded. And on some
         // devices that causes a read mode violation.
         try (StrictModeContext ignored = StrictModeContext.allowDiskReads()) {