Implement function entry breakpoints in Observatory debugger.

runtime/observatory/lib/src/service/object.dart

Index: runtime/observatory/lib/src/service/object.dart
diff --git a/runtime/observatory/lib/src/service/object.dart b/runtime/observatory/lib/src/service/object.dart
index 105709ba34237659f794ae0b1b3514ab6c9fd25b..460a372b8c43e9aacc604768266599024df4b354 100644
--- a/runtime/observatory/lib/src/service/object.dart
+++ b/runtime/observatory/lib/src/service/object.dart
@@ -1094,7 +1094,7 @@ class Isolate extends ServiceObjectOwner with Coverage {
   Future<ServiceObject> addBreakpoint(Script script, int line) {
     // TODO(turnidge): Pass line as an int instead of a string.
     Map params = {
-      'script': script.id,
+      'scriptId': script.id,
       'line': '$line',
     };
     return invokeRpc('addBreakpoint', params).then((result) {
@@ -1116,6 +1116,17 @@ class Isolate extends ServiceObjectOwner with Coverage {
     });
   }
 
+  Future<ServiceObject> addBreakpointAtEntry(ServiceFunction function) {
+    return invokeRpc('addBreakpointAtEntry',
+                     { 'functionId': function.id }).then((result) {
+        // TODO(turnidge): Instead of reloading all of the breakpoints,
+        // rely on events to update the breakpoint list.
+        return reloadBreakpoints().then((_) {
+            return result;
+        });
+      });
+  }
+
   Future removeBreakpoint(Breakpoint bpt) {
     return invokeRpc('removeBreakpoint',
                      { 'breakpointId': bpt.id }).then((result) {