Migrating to fluent logging (green).

I did some minor clean-ups of the resulting logging statements (mostly moving/adding exceptions as causes that were missed), and a few other drive-bys.

PiperOrigin-RevId: 306429419
diff --git a/src/main/java/com/google/devtools/build/lib/util/PersistentMap.java b/src/main/java/com/google/devtools/build/lib/util/PersistentMap.java
index 04cd488..e83ac86 100644
--- a/src/main/java/com/google/devtools/build/lib/util/PersistentMap.java
+++ b/src/main/java/com/google/devtools/build/lib/util/PersistentMap.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.util;
 
 import com.google.common.collect.ForwardingMap;
+import com.google.common.flogger.GoogleLogger;
 import com.google.common.io.ByteStreams;
 import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.build.lib.vfs.Path;
@@ -29,7 +30,6 @@
 import java.util.Hashtable;
 import java.util.LinkedHashMap;
 import java.util.Map;
-import java.util.logging.Logger;
 
 /**
  * A map that is backed by persistent storage. It uses two files on disk for
@@ -71,7 +71,7 @@
   private static final int ENTRY_MAGIC = 0xfe;
   private static final int MIN_MAPFILE_SIZE = 16;
   private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
-  private static final Logger logger = Logger.getLogger(PersistentMap.class.getName());
+  private static final GoogleLogger logger = GoogleLogger.forEnclosingClass();
 
   private final int version;
   private final Path mapFile;
@@ -388,7 +388,7 @@
       in.close();
     }
 
-    logger.info(String.format("Loaded cache '%s' [%s bytes]", mapFile, fileSize));
+    logger.atInfo().log("Loaded cache '%s' [%d bytes]", mapFile, fileSize);
   }
 
   /**