Add flag to disable impl-side painting

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 78df5b3bed916aaf6bf26663a03174a873193ed4..e1b4cdc9a373150262495ca7cf081ee0c5b6a92f 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -244,6 +244,14 @@ const Experiment::Choice kChromeCaptivePortalDetectionChoices[] = {
 };
 #endif
 
+const Experiment::Choice kImplSidePaintingChoices[] = {
+  { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
+  { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
+    cc::switches::kEnableImplSidePainting, ""},
+  { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
+    cc::switches::kDisableImplSidePainting, ""}
+};
+
 // RECORDING USER METRICS FOR FLAGS:
 // -----------------------------------------------------------------------------
 // The first line of the experiment is the internal name. If you'd like to
@@ -1285,6 +1293,13 @@ const Experiment kExperiments[] = {
     kOsDesktop,
     SINGLE_VALUE_TYPE(switches::kAppsDevtool)
   },
+  {
+    "impl-side-painting",
+    IDS_FLAGS_IMPL_SIDE_PAINTING_NAME,
+    IDS_FLAGS_IMPL_SIDE_PAINTING_DESCRIPTION,
+    kOsAndroid,
+    MULTI_VALUE_TYPE(kImplSidePaintingChoices)
+  },
 };
 
 const Experiment* experiments = kExperiments;