CrossSiteIFrameLinker: change installcode default for pretty mode

When using -style pretty or -style detailed, change the default
for "installcode" to false so that the cache.js files are easier
to read.

However, don't change this for optimized builds because it might
have a bad effect on latency for some apps; it's hard to tell
without doing extensive testing.

Most apps shouldn't care about this, but where it matters, the
default can be explicitly overridden:

  <set-configuration-property name="installCode" value="true" />

Change-Id: I98a15ed8c47362c014680e6cddfdab9c1755e67a
diff --git a/dev/core/src/com/google/gwt/core/linker/CrossSiteIframeLinker.java b/dev/core/src/com/google/gwt/core/linker/CrossSiteIframeLinker.java
index a900f6c..79e9eaa 100644
--- a/dev/core/src/com/google/gwt/core/linker/CrossSiteIframeLinker.java
+++ b/dev/core/src/com/google/gwt/core/linker/CrossSiteIframeLinker.java
@@ -629,7 +629,7 @@
    * as a list of strings and then adds it to the iframe.
    */
   protected boolean shouldInstallCode(LinkerContext context) {
-    return getBooleanConfigurationProperty(context, "installCode", true);
+    return getBooleanConfigurationProperty(context, "installCode", context.isOutputCompact());
   }
 
   /**