Revert of cc: Remove WorkerPool class and instead use TaskGraphRunner directly.

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 12bcf7990f64e80f23b2e7064bfe2ac4d22f5317..b41c3af29662e30a8ef510524f6989dbb1055864 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -328,10 +328,10 @@
 
 const Experiment::Choice kNumRasterThreadsChoices[] = {
   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
-  { IDS_FLAGS_NUM_RASTER_THREADS_ONE, switches::kNumRasterThreads, "1" },
-  { IDS_FLAGS_NUM_RASTER_THREADS_TWO, switches::kNumRasterThreads, "2" },
-  { IDS_FLAGS_NUM_RASTER_THREADS_THREE, switches::kNumRasterThreads, "3" },
-  { IDS_FLAGS_NUM_RASTER_THREADS_FOUR, switches::kNumRasterThreads, "4" }
+  { IDS_FLAGS_NUM_RASTER_THREADS_ONE, cc::switches::kNumRasterThreads, "1" },
+  { IDS_FLAGS_NUM_RASTER_THREADS_TWO, cc::switches::kNumRasterThreads, "2" },
+  { IDS_FLAGS_NUM_RASTER_THREADS_THREE, cc::switches::kNumRasterThreads, "3" },
+  { IDS_FLAGS_NUM_RASTER_THREADS_FOUR, cc::switches::kNumRasterThreads, "4" }
 };
 
 // We're using independent flags here (as opposed to a common flag with