Remove incorrect assertion in assertNoMessageThatMatches.

Change-Id: I1dc0ca539facf3b5f391b2e66ebceed9fc157b12

src/test/java/com/android/tools/r8/TestDiagnosticMessagesImpl.java

diff --git a/src/test/java/com/android/tools/r8/TestDiagnosticMessagesImpl.java b/src/test/java/com/android/tools/r8/TestDiagnosticMessagesImpl.java
index 3082da8..8282c77 100644
--- a/src/test/java/com/android/tools/r8/TestDiagnosticMessagesImpl.java
+++ b/src/test/java/com/android/tools/r8/TestDiagnosticMessagesImpl.java
@@ -147,7 +147,6 @@
 
   private TestDiagnosticMessages assertNoMessageThatMatches(
       List<Diagnostic> diagnostics, String tag, Matcher<String> matcher) {
-    assertNotEquals(0, diagnostics.size());
     for (int i = 0; i < diagnostics.size(); i++) {
       String message = diagnostics.get(i).getDiagnosticMessage();
       if (matcher.matches(message)) {