Shared Highlighting default color

This CL adds to the shared highlighting component a constant default color (light purple) code.

Bug: 1166249
Change-Id: Id4c56a010f3f2e80be6f1989b05ec3e0cb88a7e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2633009Reviewed-by: Sebastien Lalancette <seblalancette@chromium.org>
Reviewed-by: Tommy Martino <tmartino@chromium.org>
Reviewed-by: sebsg <sebsg@chromium.org>
Commit-Queue: Cheick Cisse <cheickcisse@google.com>
Cr-Commit-Position: refs/heads/master@{#844531}

components/shared_highlighting/core/common/text_fragments_constants.cc

@@ -15,4 +15,7 @@ const char kFragmentTextStartKey[] = "textStart";
 const char kFragmentTextEndKey[] = "textEnd";
 const char kFragmentSuffixKey[] = "suffix";
 
+// Light purple.
+const int kSharedHighlightingColorRGB[] = {233, 210, 253};
+
 }  // namespace shared_highlighting

components/shared_highlighting/core/common/text_fragments_constants.h

@@ -20,6 +20,9 @@ extern const char kFragmentTextStartKey[];
 extern const char kFragmentTextEndKey[];
 extern const char kFragmentSuffixKey[];
 
+// Default highlight color.
+extern const int kSharedHighlightingColorRGB[];
+
 }  // namespace shared_highlighting
 
 #endif  // COMPONENTS_SHARED_HIGHLIGHTING_CORE_COMMON_TEXT_FRAGMENTS_CONSTANTS_H_