Refactor exception-message assertions to use ThrowableSubject.hasMessageThat(). This replaces assertions of the form assertThat(e).hasMessage(...) and assertThat(e.getMessage()) with assertThat(e).hasMessageThat().

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239181584
diff --git a/common/src/test/java/com/google/auto/common/AnnotationMirrorsTest.java b/common/src/test/java/com/google/auto/common/AnnotationMirrorsTest.java
index c1857b7..d5609a2 100644
--- a/common/src/test/java/com/google/auto/common/AnnotationMirrorsTest.java
+++ b/common/src/test/java/com/google/auto/common/AnnotationMirrorsTest.java
@@ -199,8 +199,10 @@
     try {
       AnnotationMirrors.getAnnotationValue(annotationOn(TestClassBlah.class), "a");
     } catch (IllegalArgumentException e) {
-      assertThat(e).hasMessage(
-          "@com.google.auto.common.AnnotationMirrorsTest.Outer does not define an element a()");
+      assertThat(e)
+          .hasMessageThat()
+          .isEqualTo(
+              "@com.google.auto.common.AnnotationMirrorsTest.Outer does not define an element a()");
       return;
     }
     fail("Should have thrown.");
diff --git a/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueJava8Test.java b/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueJava8Test.java
index 13c6d80..336fadb 100644
--- a/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueJava8Test.java
+++ b/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueJava8Test.java
@@ -525,13 +525,13 @@
       builder.list();
       fail("Attempt to retrieve unset list property should have failed");
     } catch (IllegalStateException e) {
-      assertThat(e).hasMessage("Property \"list\" has not been set");
+      assertThat(e).hasMessageThat().isEqualTo("Property \"list\" has not been set");
     }
     try {
       builder.ints();
       fail("Attempt to retrieve unset ints property should have failed");
     } catch (IllegalStateException e) {
-      assertThat(e).hasMessage("Property \"ints\" has not been set");
+      assertThat(e).hasMessageThat().isEqualTo("Property \"ints\" has not been set");
     }
 
     builder.setList(names);
@@ -599,7 +599,7 @@
       builder.getList();
       fail("Attempt to retrieve unset list property should have failed");
     } catch (IllegalStateException e) {
-      assertThat(e).hasMessage("Property \"list\" has not been set");
+      assertThat(e).hasMessageThat().isEqualTo("Property \"list\" has not been set");
     }
 
     builder.setList(names);
diff --git a/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueTest.java b/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueTest.java
index 4b37916..0c7bfea 100644
--- a/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueTest.java
+++ b/value/src/it/functional/src/test/java/com/google/auto/value/AutoValueTest.java
@@ -1923,7 +1923,7 @@
       if (omitIdentifiers) {
         assertThat(e).hasMessageThat().isNull();
       } else {
-        assertThat(e).hasMessage("Property \"list\" has not been set");
+        assertThat(e).hasMessageThat().isEqualTo("Property \"list\" has not been set");
       }
     }
     try {
@@ -1933,7 +1933,7 @@
       if (omitIdentifiers) {
         assertThat(e).hasMessageThat().isNull();
       } else {
-        assertThat(e).hasMessage("Property \"ints\" has not been set");
+        assertThat(e).hasMessageThat().isEqualTo("Property \"ints\" has not been set");
       }
     }
 
@@ -2014,7 +2014,7 @@
       if (omitIdentifiers) {
         assertThat(e).hasMessageThat().isNull();
       } else {
-        assertThat(e).hasMessage("Property \"list\" has not been set");
+        assertThat(e).hasMessageThat().isEqualTo("Property \"list\" has not been set");
       }
     }
 
@@ -2307,7 +2307,7 @@
       if (omitIdentifiers) {
         assertThat(e).hasMessageThat().isNull();
       } else {
-        assertThat(e).hasMessage("Cannot set things after calling thingsBuilder()");
+        assertThat(e).hasMessageThat().isEqualTo("Cannot set things after calling thingsBuilder()");
       }
     }
   }
diff --git a/value/src/test/java/com/google/auto/value/extension/memoized/MemoizedTest.java b/value/src/test/java/com/google/auto/value/extension/memoized/MemoizedTest.java
index a8ea3e3..bc4895e 100644
--- a/value/src/test/java/com/google/auto/value/extension/memoized/MemoizedTest.java
+++ b/value/src/test/java/com/google/auto/value/extension/memoized/MemoizedTest.java
@@ -274,7 +274,9 @@
       value.notNullableButReturnsNull();
       fail();
     } catch (NullPointerException expected) {
-      assertThat(expected).hasMessage("notNullableButReturnsNull() cannot return null");
+      assertThat(expected)
+          .hasMessageThat()
+          .isEqualTo("notNullableButReturnsNull() cannot return null");
     }
     assertThat(value.notNullableButReturnsNullCount).isEqualTo(1);
   }