flag: restore show-overdraw-feedback flag

This CL reverts the removal of the show-overdraw-feedback
flag that was removed in
https://chromium-review.googlesource.com/c/chromium/src/+/1529513

Bug: 1025119
Test: Open chrome://flags and verify the flag is there.
Change-Id: I3410097067e2f607bcf68bc8a0534e45c6facf10
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1967194
Commit-Queue: Paulo Warren <pwarren@google.com>
Reviewed-by: Miguel Casas <mcasas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#724722}

chrome/browser/about_flags.cc

@@ -1482,6 +1482,9 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kTintGlCompositedContentName,
      flag_descriptions::kTintGlCompositedContentDescription, kOsAll,
      SINGLE_VALUE_TYPE(switches::kTintGlCompositedContent)},
+    {"show-overdraw-feedback", flag_descriptions::kShowOverdrawFeedbackName,
+     flag_descriptions::kShowOverdrawFeedbackDescription, kOsAll,
+     SINGLE_VALUE_TYPE(switches::kShowOverdrawFeedback)},
     {"ui-disable-partial-swap", flag_descriptions::kUiPartialSwapName,
      flag_descriptions::kUiPartialSwapDescription, kOsAll,
      SINGLE_DISABLE_VALUE_TYPE(switches::kUIDisablePartialSwap)},

chrome/browser/flag-metadata.json

@@ -3281,6 +3281,11 @@
     "owners": [ "cthomp" ],
     "expiry_milestone": 85
   },
+  {
+    "name": "show-overdraw-feedback",
+    "owners": [ "andrescj", "chromeos-gfx@google.com" ],
+    "expiry_milestone": 85
+  },
   {
     "name": "show-sync-paused-reason-cookies-cleared-on-exit",
     "owners": [ "msalama" ],

chrome/browser/flag_descriptions.cc

@@ -1935,6 +1935,11 @@ const char kShowAutofillTypePredictionsDescription[] =
     "Annotates web forms with Autofill field type predictions as placeholder "
     "text.";
 
+const char kShowOverdrawFeedbackName[] = "Show overdraw feedback";
+const char kShowOverdrawFeedbackDescription[] =
+    "Visualize overdraw by color-coding elements based on if they have other "
+    "elements drawn underneath.";
+
 const char kSkiaRendererName[] = "Skia API for OOP-D compositing";
 const char kSkiaRendererDescription[] =
     "If enabled, the display compositor will use Skia as the graphics API "

chrome/browser/flag_descriptions.h

@@ -1138,6 +1138,9 @@ extern const char kShowAutofillSignaturesDescription[];
 extern const char kShowAutofillTypePredictionsName[];
 extern const char kShowAutofillTypePredictionsDescription[];
 
+extern const char kShowOverdrawFeedbackName[];
+extern const char kShowOverdrawFeedbackDescription[];
+
 extern const char kSkiaRendererName[];
 extern const char kSkiaRendererDescription[];