[conversions] Add about flags entries for API and debug mode

Adds about flag entries for enabling the API as well as the debug mode
version. Exposed for developer testing.

Bug: 1082421
Change-Id: Ib68277248ba35c563932d7d296cce6b74e77ad66
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2198645
Commit-Queue: John Delaney <[email protected]>
Reviewed-by: Charlie Harrison <[email protected]>
Cr-Commit-Position: refs/heads/master@{#768515}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 41bf756f..cede3145 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -76,6 +76,12 @@
 extern const char kAllowSyncXHRInPageDismissalName[];
 extern const char kAllowSyncXHRInPageDismissalDescription[];
 
+extern const char kConversionMeasurementApiName[];
+extern const char kConversionMeasurementApiDescription[];
+
+extern const char kConversionMeasurementDebugModeName[];
+extern const char kConversionMeasurementDebugModeDescription[];
+
 extern const char kEnableClipboardProviderImageSuggestionsName[];
 extern const char kEnableClipboardProviderImageSuggestionsDescription[];