Bug 1510988 - Make the clear flag optional in snapshot API r=chutten

Differential Revision: https://phabricator.services.mozilla.com/D16966

--HG--
extra : moz-landing-system : lando

toolkit/components/telemetry/core/nsITelemetry.idl

@@ -66,12 +66,13 @@ interface nsITelemetry : nsISupports
    *
    * @param aStoreName The name of the store to snapshot. Something like "main".
    * @param aClearStore Whether to clear out the histograms in the named store after snapshotting.
+   *                    Defaults to false.
    * @param aFilterTest If true, `TELEMETRY_TEST_` histograms will be filtered out.
                         Filtered histograms are still cleared if `aClearStore` is true.
    *                    Defaults to false.
    */
   [implicit_jscontext]
-  jsval getSnapshotForHistograms(in ACString aStoreName, in boolean aClearStore, [optional] in boolean aFilterTest);
+  jsval getSnapshotForHistograms(in ACString aStoreName, [optional] in boolean aClearStore, [optional] in boolean aFilterTest);
 
   /**
    * Serializes the keyed histograms from the given store to a JSON-style object.
@@ -80,12 +81,13 @@ interface nsITelemetry : nsISupports
    *
    * @param aStoreName The name of the store to snapshot. Something like "main".
    * @param aClearStore Whether to clear out the keyed histograms in the named store after snapshotting.
+   *                    Defaults to false.
    * @param aFilterTest If true, `TELEMETRY_TEST_` histograms will be filtered out.
                         Filtered histograms are still cleared if `aClearStore` is true.
    *                    Defaults to false.
    */
   [implicit_jscontext]
-  jsval getSnapshotForKeyedHistograms(in ACString aStoreName, in boolean aClearStore, [optional] in boolean aFilterTest);
+  jsval getSnapshotForKeyedHistograms(in ACString aStoreName, [optional] in boolean aClearStore, [optional] in boolean aFilterTest);
 
   /**
    * Serializes the scalars from the given store to a JSON-style object.
@@ -94,12 +96,13 @@ interface nsITelemetry : nsISupports
    *
    * @param aStoreName The name of the store to snapshot. Something like "main".
    * @param aClearStore Whether to clear out the scalars in the named store after snapshotting.
+   *                    Defaults to false.
    * @param aFilterTest If true, `telemetry.test` scalars will be filtered out.
                         Filtered scalars are still cleared if `aClearStore` is true.
    *                    Defaults to false.
    */
   [implicit_jscontext]
-  jsval getSnapshotForScalars(in ACString aStoreName, in boolean aClearStore, [optional] in boolean aFilterTest);
+  jsval getSnapshotForScalars(in ACString aStoreName, [optional] in boolean aClearStore, [optional] in boolean aFilterTest);
 
   /**
    * Serializes the keyed scalars from the given store to a JSON-style object.
@@ -108,12 +111,13 @@ interface nsITelemetry : nsISupports
    *
    * @param aStoreName The name of the store to snapshot. Something like "main".
    * @param aClearStore Whether to clear out the keyed scalars in the named store after snapshotting.
+   *                    Defaults to false.
    * @param aFilterTest If true, `telemetry.test` scalars will be filtered out.
                         Filtered scalars are still cleared if `aClearStore` is true.
    *                    Defaults to false.
    */
   [implicit_jscontext]
-  jsval getSnapshotForKeyedScalars(in ACString aStoreName, in boolean aClearStore, [optional] in boolean aFilterTest);
+  jsval getSnapshotForKeyedScalars(in ACString aStoreName, [optional] in boolean aClearStore, [optional] in boolean aFilterTest);
 
   /**
    * The amount of time, in milliseconds, that the last session took