Log number of known dependencies if Dependency throws an exception

This can provide a modicum of insight into why Dependency may be failing
to retrieve the required class. If, for instance, there is a race
condition then we would expect to see a smaller number of known
dependencies.

Dependency.

Bug: 65560049
Test: request a non-registered depdency from Depdency.java, then read
the logs.

Change-Id: I583287d0b59da321ab590f53a86c2d9b357304b2

1 files changed, 2 insertions, 1 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/Dependency.java b/packages/SystemUI/src/com/android/systemui/Dependency.java
index a9a915b23a0c..2937a250140a 100644
--- a/packages/SystemUI/src/com/android/systemui/Dependency.java
+++ b/packages/SystemUI/src/com/android/systemui/Dependency.java
@@ -348,7 +348,8 @@ public class Dependency extends SystemUI {
         @SuppressWarnings("unchecked")
         DependencyProvider<T> provider = mProviders.get(cls);
         if (provider == null) {
-            throw new IllegalArgumentException("Unsupported dependency " + cls);
+            throw new IllegalArgumentException("Unsupported dependency " + cls
+                    + ". " + mProviders.size() + " providers known.");
         }
         return provider.createDependency();
     }