speech: Update recognition-service resource

Adding an attribute to the recognition-service resource which will
limit the maximum number of concurrent sessions ongoing with the same
recognition implementation. The default value of attribute is 1
(no concurrency), maintaining the back-compatibility.

Each recognition service implementation can override this value for
itself to the extent they find suitable.

Bug: 260713947
Test: n/a
Change-Id: I84d4856c8bb99a73f2b542c207429c5dcc7e1e91

core/api/current.txt

@@ -1041,6 +1041,7 @@ package android {
     field public static final int max = 16843062; // 0x1010136
     field public static final int maxAspectRatio = 16844128; // 0x1010560
     field public static final int maxButtonHeight = 16844029; // 0x10104fd
+    field public static final int maxConcurrentSessionsCount;
     field public static final int maxDate = 16843584; // 0x1010340
     field public static final int maxEms = 16843095; // 0x1010157
     field public static final int maxHeight = 16843040; // 0x1010120

core/res/res/values/attrs.xml

@@ -8955,6 +8955,9 @@
         <!-- Flag indicating whether a recognition service can be selected as default. The default
              value of this flag is true. -->
         <attr name="selectableAsDefault" format="boolean" />
+        <!-- The maximal number of recognition sessions ongoing at the same time.
+             The default value is 1, meaning no concurrency. -->
+        <attr name="maxConcurrentSessionsCount" format="integer" />
     </declare-styleable>
 
     <!-- Use <code>voice-interaction-service</code> as the root tag of the XML resource that

core/res/res/values/public-staging.xml

@@ -117,6 +117,7 @@
     <public name="accessibilityDataPrivate" />
     <public name="enableTextStylingShortcuts" />
     <public name="targetDisplayCategory"/>
+    <public name="maxConcurrentSessionsCount" />
   </staging-public-group>
 
   <staging-public-group type="id" first-id="0x01cd0000">