diff --git a/core/java/android/app/ApplicationErrorReport.java b/core/java/android/app/ApplicationErrorReport.java
index 6524c9a..588125d 100644
--- a/core/java/android/app/ApplicationErrorReport.java
+++ b/core/java/android/app/ApplicationErrorReport.java
@@ -332,20 +332,31 @@
             exceptionMessage = tr.getMessage();
 
             // Populate fields with the "root cause" exception
+            Throwable rootTr = tr;
             while (tr.getCause() != null) {
                 tr = tr.getCause();
+                if (tr.getStackTrace() != null && tr.getStackTrace().length > 0) {
+                    rootTr = tr;
+                }
                 String msg = tr.getMessage();
                 if (msg != null && msg.length() > 0) {
                     exceptionMessage = msg;
                 }
             }
 
-            exceptionClassName = tr.getClass().getName();
-            StackTraceElement trace = tr.getStackTrace()[0];
-            throwFileName = trace.getFileName();
-            throwClassName = trace.getClassName();
-            throwMethodName = trace.getMethodName();
-            throwLineNumber = trace.getLineNumber();
+            exceptionClassName = rootTr.getClass().getName();
+            if (rootTr.getStackTrace().length > 0) {
+                StackTraceElement trace = rootTr.getStackTrace()[0];
+                throwFileName = trace.getFileName();
+                throwClassName = trace.getClassName();
+                throwMethodName = trace.getMethodName();
+                throwLineNumber = trace.getLineNumber();
+            } else {
+                throwFileName = "unknown";
+                throwClassName = "unknown";
+                throwMethodName = "unknown";
+                throwLineNumber = 0;
+            }
         }
 
         /**
diff --git a/core/java/android/net/Uri.java b/core/java/android/net/Uri.java
index 3b21590..2c875c8 100644
--- a/core/java/android/net/Uri.java
+++ b/core/java/android/net/Uri.java
@@ -1689,7 +1689,7 @@
                     return HierarchicalUri.readFrom(in);
             }
 
-            throw new AssertionError("Unknown URI type: " + type);
+            throw new IllegalArgumentException("Unknown URI type: " + type);
         }
 
         public Uri[] newArray(int size) {
@@ -1996,7 +1996,7 @@
                 parcel.writeInt(Representation.DECODED);
                 parcel.writeString(decoded);
             } else {
-                throw new AssertionError();
+                throw new IllegalArgumentException("Neither encoded nor decoded");
             }
         }
     }
@@ -2037,7 +2037,8 @@
                 case Representation.DECODED:
                     return fromDecoded(parcel.readString());
                 default:
-                    throw new AssertionError();
+                    throw new IllegalArgumentException("Unknown representation: "
+                            + representation);
             }
         }
 
@@ -2221,7 +2222,7 @@
                 case Representation.DECODED:
                     return fromDecoded(parcel.readString());
                 default:
-                    throw new AssertionError();
+                    throw new IllegalArgumentException("Bad representation: " + representation);
             }
         }
 
diff --git a/core/java/com/android/internal/os/ProcessStats.java b/core/java/com/android/internal/os/ProcessStats.java
index ea5ce09..e0e9a29 100644
--- a/core/java/com/android/internal/os/ProcessStats.java
+++ b/core/java/com/android/internal/os/ProcessStats.java
@@ -19,6 +19,7 @@
 import static android.os.Process.*;
 
 import android.os.Process;
+import android.os.StrictMode;
 import android.os.SystemClock;
 import android.util.Slog;
 
@@ -798,6 +799,10 @@
     }
     
     private String readFile(String file, char endChar) {
+        // Permit disk reads here, as /proc/meminfo isn't really "on
+        // disk" and should be fast.  TODO: make BlockGuard ignore
+        // /proc/ and /sys/ files perhaps?
+        StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
         FileInputStream is = null;
         try {
             is = new FileInputStream(file);
@@ -822,6 +827,7 @@
                 } catch (java.io.IOException e) {
                 }
             }
+            StrictMode.setThreadPolicy(savedPolicy);
         }
         return null;
     }
diff --git a/services/java/com/android/server/am/ActivityStack.java b/services/java/com/android/server/am/ActivityStack.java
index 33b21ab..ee0937d 100644
--- a/services/java/com/android/server/am/ActivityStack.java
+++ b/services/java/com/android/server/am/ActivityStack.java
@@ -276,10 +276,12 @@
         public void handleMessage(Message msg) {
             switch (msg.what) {
                 case SLEEP_TIMEOUT_MSG: {
-                    if (mService.isSleeping()) {
-                        Slog.w(TAG, "Sleep timeout!  Sleeping now.");
-                        mSleepTimeout = true;
-                        checkReadyForSleepLocked();
+                    synchronized (mService) {
+                        if (mService.isSleeping()) {
+                            Slog.w(TAG, "Sleep timeout!  Sleeping now.");
+                            mSleepTimeout = true;
+                            checkReadyForSleepLocked();
+                        }
                     }
                 } break;
                 case PAUSE_TIMEOUT_MSG: {
@@ -775,7 +777,6 @@
         if (mService.mShuttingDown) {
             mService.notifyAll();
         }
-
     }
     
     public final Bitmap screenshotActivities(ActivityRecord who) {
diff --git a/services/java/com/android/server/wm/WindowManagerService.java b/services/java/com/android/server/wm/WindowManagerService.java
index 0a6e89e..558ba3e 100644
--- a/services/java/com/android/server/wm/WindowManagerService.java
+++ b/services/java/com/android/server/wm/WindowManagerService.java
@@ -8736,6 +8736,12 @@
             return;
         }
 
+        if (mDisplay == null || !mPolicy.isScreenOn()) {
+            // No need to freeze the screen before the system is ready or if
+            // the screen is off.
+            return;
+        }
+
         mScreenFrozenLock.acquire();
 
         mDisplayFrozen = true;