Reland "Roll R8 2.0.2 -> 2.1.8"

Added keeps required to keep Mockito happy - revert happened here:
https://crbug.com/1056619.

This is a reland of 2d6ff560

Original change's description:
> Roll R8 2.0.2 -> 2.1.8
>
> I checked to ensure crbug.com/1050440 was fixed.
> https://issuetracker.google.com/149831282
>
> Bug: 1040534
> Change-Id: I3894f4316f2dde2527a35ad6e919ee8cdc86c2b9
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2075039
> Commit-Queue: Andrew Grieve <agrieve@chromium.org>
> Reviewed-by: Andrew Grieve <agrieve@chromium.org>
> Auto-Submit: Sam Maier <smaier@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#744708}

Bug: 1040534
Change-Id: Ia991b83ef942d6655f9e1ba561ab1b407025ccae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2078591
Commit-Queue: Sam Maier <smaier@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745189}

DEPS

@@ -1333,7 +1333,7 @@ deps = {
       'packages': [
           {
               'package': 'chromium/third_party/r8',
-              'version': '-oXGY8FjY2ZuIBHoGAByn8N6Vn2b0wB2QO8Ct_169XoC',
+              'version': 'C28ypVbWD-R2M9x9fH7QniIsYjJrKoUhxqEV_cZR4qgC',
           },
       ],
       'condition': 'checkout_android',

testing/android/proguard_for_test.flags

@@ -37,6 +37,16 @@
   <methods>;
 }
 
+# This is a workaround for b/147584922 - otherwise, R8 would generate a synthetic
+# abstract method for the subsclass FeedOfflineIndicator, which Mockito would not
+# mock.
+-keep interface **.feed**.OfflineIndicatorApi {
+  <methods>;
+}
+-keep interface **.feed**.SchedulerApi {
+  <methods>;
+}
+
 # Keep all enum members since they might be reflectively called by JUnit4 runner
 -keepclassmembers enum * { *; }
 

third_party/r8/README.chromium

 Name: R8
 URL: https://r8.googlesource.com/r8
-Revision: 5cca4af33d246f51b49650d7480493247947eda9
-Version: 2.0.2-dev
+Revision: cc4b64009b85ce83b072e62e30bd4c2accaec5be
+Version: 2.1.8-dev
 License: BSD 3-Clause
 License File: NOT_SHIPPED
 Security Critical: no

third_party/r8/local_modifications.diff

 diff --git a/src/main/java/com/android/tools/r8/utils/InternalOptions.java b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
-index 595ac28da..e96f06364 100644
+index 232b54a54..5c3a227b3 100644
 --- a/src/main/java/com/android/tools/r8/utils/InternalOptions.java
 +++ b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
-@@ -194,8 +194,8 @@ public class InternalOptions {
-   public boolean enableDynamicTypeOptimization = true;
+@@ -198,8 +198,8 @@ public class InternalOptions {
+   public boolean enableFieldAssignmentTracker = true;
    public boolean enableFieldBitAccessAnalysis =
        System.getProperty("com.android.tools.r8.fieldBitAccessAnalysis") != null;
 -  public boolean enableHorizontalClassMerging = true;
 -  public boolean enableVerticalClassMerging = true;
-+  public boolean enableHorizontalClassMerging = false;
-+  public boolean enableVerticalClassMerging = false;
++  public boolean enableHorizontalClassMerging = System.getProperty("com.android.tools.r8.enableClassMerging") != null;
++  public boolean enableVerticalClassMerging = System.getProperty("com.android.tools.r8.enableClassMerging") != null;
    public boolean enableArgumentRemoval = true;
    public boolean enableUnusedArgumentRemoval = true;
    public boolean enableUnusedInterfaceRemoval = true;
-@@ -919,7 +919,7 @@ public class InternalOptions {
+@@ -956,7 +956,7 @@ public class InternalOptions {
      public static final String CLASS_NAME = "com.android.tools.r8.GeneratedOutlineSupport";
      public static final String METHOD_PREFIX = "outline";