Use the smallest image within srcset for data saver users.

This selects the smallest image within a srcset for data saver users.
This creates a feature flag to control this functionality.

Bug: 606941
Change-Id: I1cbb6e543035d9803bb041fb9df1e5cd8c286801
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2044810
Reviewed-by: rajendrant <[email protected]>
Reviewed-by: Yoav Weiss <[email protected]>
Reviewed-by: Kinuko Yasuda <[email protected]>
Reviewed-by: Tarun Bansal <[email protected]>
Commit-Queue: Michael Crouse <[email protected]>
Cr-Commit-Position: refs/heads/master@{#742938}
diff --git a/third_party/blink/common/features.cc b/third_party/blink/common/features.cc
index a763fb7..00034bce 100644
--- a/third_party/blink/common/features.cc
+++ b/third_party/blink/common/features.cc
@@ -298,6 +298,11 @@
 const base::Feature kForceWebContentsDarkMode{
     "WebContentsForceDark", base::FEATURE_DISABLED_BY_DEFAULT};
 
+// A feature to enable using the smallest image specified within image srcset
+// for users with Save Data enabled.
+const base::Feature kSaveDataImgSrcset{"SaveDataImgSrcset",
+                                       base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Which algorithm should be used for color inversion?
 const base::FeatureParam<ForceDarkInversionMethod>::Option
     forcedark_inversion_method_options[] = {